1 //===-- TargetLowering.cpp - Implement the TargetLowering class -----------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This implements the TargetLowering class.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/Target/TargetLowering.h"
15 #include "llvm/MC/MCAsmInfo.h"
16 #include "llvm/MC/MCExpr.h"
17 #include "llvm/Target/TargetData.h"
18 #include "llvm/Target/TargetLoweringObjectFile.h"
19 #include "llvm/Target/TargetMachine.h"
20 #include "llvm/Target/TargetRegisterInfo.h"
21 #include "llvm/Target/TargetSubtarget.h"
22 #include "llvm/GlobalVariable.h"
23 #include "llvm/DerivedTypes.h"
24 #include "llvm/CodeGen/MachineFrameInfo.h"
25 #include "llvm/CodeGen/MachineJumpTableInfo.h"
26 #include "llvm/CodeGen/MachineFunction.h"
27 #include "llvm/CodeGen/SelectionDAG.h"
28 #include "llvm/ADT/STLExtras.h"
29 #include "llvm/Support/ErrorHandling.h"
30 #include "llvm/Support/MathExtras.h"
34 TLSModel::Model getTLSModel(const GlobalValue *GV, Reloc::Model reloc) {
35 bool isLocal = GV->hasLocalLinkage();
36 bool isDeclaration = GV->isDeclaration();
37 // FIXME: what should we do for protected and internal visibility?
38 // For variables, is internal different from hidden?
39 bool isHidden = GV->hasHiddenVisibility();
41 if (reloc == Reloc::PIC_) {
42 if (isLocal || isHidden)
43 return TLSModel::LocalDynamic;
45 return TLSModel::GeneralDynamic;
47 if (!isDeclaration || isHidden)
48 return TLSModel::LocalExec;
50 return TLSModel::InitialExec;
55 /// InitLibcallNames - Set default libcall names.
57 static void InitLibcallNames(const char **Names) {
58 Names[RTLIB::SHL_I16] = "__ashlhi3";
59 Names[RTLIB::SHL_I32] = "__ashlsi3";
60 Names[RTLIB::SHL_I64] = "__ashldi3";
61 Names[RTLIB::SHL_I128] = "__ashlti3";
62 Names[RTLIB::SRL_I16] = "__lshrhi3";
63 Names[RTLIB::SRL_I32] = "__lshrsi3";
64 Names[RTLIB::SRL_I64] = "__lshrdi3";
65 Names[RTLIB::SRL_I128] = "__lshrti3";
66 Names[RTLIB::SRA_I16] = "__ashrhi3";
67 Names[RTLIB::SRA_I32] = "__ashrsi3";
68 Names[RTLIB::SRA_I64] = "__ashrdi3";
69 Names[RTLIB::SRA_I128] = "__ashrti3";
70 Names[RTLIB::MUL_I8] = "__mulqi3";
71 Names[RTLIB::MUL_I16] = "__mulhi3";
72 Names[RTLIB::MUL_I32] = "__mulsi3";
73 Names[RTLIB::MUL_I64] = "__muldi3";
74 Names[RTLIB::MUL_I128] = "__multi3";
75 Names[RTLIB::SDIV_I8] = "__divqi3";
76 Names[RTLIB::SDIV_I16] = "__divhi3";
77 Names[RTLIB::SDIV_I32] = "__divsi3";
78 Names[RTLIB::SDIV_I64] = "__divdi3";
79 Names[RTLIB::SDIV_I128] = "__divti3";
80 Names[RTLIB::UDIV_I8] = "__udivqi3";
81 Names[RTLIB::UDIV_I16] = "__udivhi3";
82 Names[RTLIB::UDIV_I32] = "__udivsi3";
83 Names[RTLIB::UDIV_I64] = "__udivdi3";
84 Names[RTLIB::UDIV_I128] = "__udivti3";
85 Names[RTLIB::SREM_I8] = "__modqi3";
86 Names[RTLIB::SREM_I16] = "__modhi3";
87 Names[RTLIB::SREM_I32] = "__modsi3";
88 Names[RTLIB::SREM_I64] = "__moddi3";
89 Names[RTLIB::SREM_I128] = "__modti3";
90 Names[RTLIB::UREM_I8] = "__umodqi3";
91 Names[RTLIB::UREM_I16] = "__umodhi3";
92 Names[RTLIB::UREM_I32] = "__umodsi3";
93 Names[RTLIB::UREM_I64] = "__umoddi3";
94 Names[RTLIB::UREM_I128] = "__umodti3";
95 Names[RTLIB::NEG_I32] = "__negsi2";
96 Names[RTLIB::NEG_I64] = "__negdi2";
97 Names[RTLIB::ADD_F32] = "__addsf3";
98 Names[RTLIB::ADD_F64] = "__adddf3";
99 Names[RTLIB::ADD_F80] = "__addxf3";
100 Names[RTLIB::ADD_PPCF128] = "__gcc_qadd";
101 Names[RTLIB::SUB_F32] = "__subsf3";
102 Names[RTLIB::SUB_F64] = "__subdf3";
103 Names[RTLIB::SUB_F80] = "__subxf3";
104 Names[RTLIB::SUB_PPCF128] = "__gcc_qsub";
105 Names[RTLIB::MUL_F32] = "__mulsf3";
106 Names[RTLIB::MUL_F64] = "__muldf3";
107 Names[RTLIB::MUL_F80] = "__mulxf3";
108 Names[RTLIB::MUL_PPCF128] = "__gcc_qmul";
109 Names[RTLIB::DIV_F32] = "__divsf3";
110 Names[RTLIB::DIV_F64] = "__divdf3";
111 Names[RTLIB::DIV_F80] = "__divxf3";
112 Names[RTLIB::DIV_PPCF128] = "__gcc_qdiv";
113 Names[RTLIB::REM_F32] = "fmodf";
114 Names[RTLIB::REM_F64] = "fmod";
115 Names[RTLIB::REM_F80] = "fmodl";
116 Names[RTLIB::REM_PPCF128] = "fmodl";
117 Names[RTLIB::POWI_F32] = "__powisf2";
118 Names[RTLIB::POWI_F64] = "__powidf2";
119 Names[RTLIB::POWI_F80] = "__powixf2";
120 Names[RTLIB::POWI_PPCF128] = "__powitf2";
121 Names[RTLIB::SQRT_F32] = "sqrtf";
122 Names[RTLIB::SQRT_F64] = "sqrt";
123 Names[RTLIB::SQRT_F80] = "sqrtl";
124 Names[RTLIB::SQRT_PPCF128] = "sqrtl";
125 Names[RTLIB::LOG_F32] = "logf";
126 Names[RTLIB::LOG_F64] = "log";
127 Names[RTLIB::LOG_F80] = "logl";
128 Names[RTLIB::LOG_PPCF128] = "logl";
129 Names[RTLIB::LOG2_F32] = "log2f";
130 Names[RTLIB::LOG2_F64] = "log2";
131 Names[RTLIB::LOG2_F80] = "log2l";
132 Names[RTLIB::LOG2_PPCF128] = "log2l";
133 Names[RTLIB::LOG10_F32] = "log10f";
134 Names[RTLIB::LOG10_F64] = "log10";
135 Names[RTLIB::LOG10_F80] = "log10l";
136 Names[RTLIB::LOG10_PPCF128] = "log10l";
137 Names[RTLIB::EXP_F32] = "expf";
138 Names[RTLIB::EXP_F64] = "exp";
139 Names[RTLIB::EXP_F80] = "expl";
140 Names[RTLIB::EXP_PPCF128] = "expl";
141 Names[RTLIB::EXP2_F32] = "exp2f";
142 Names[RTLIB::EXP2_F64] = "exp2";
143 Names[RTLIB::EXP2_F80] = "exp2l";
144 Names[RTLIB::EXP2_PPCF128] = "exp2l";
145 Names[RTLIB::SIN_F32] = "sinf";
146 Names[RTLIB::SIN_F64] = "sin";
147 Names[RTLIB::SIN_F80] = "sinl";
148 Names[RTLIB::SIN_PPCF128] = "sinl";
149 Names[RTLIB::COS_F32] = "cosf";
150 Names[RTLIB::COS_F64] = "cos";
151 Names[RTLIB::COS_F80] = "cosl";
152 Names[RTLIB::COS_PPCF128] = "cosl";
153 Names[RTLIB::POW_F32] = "powf";
154 Names[RTLIB::POW_F64] = "pow";
155 Names[RTLIB::POW_F80] = "powl";
156 Names[RTLIB::POW_PPCF128] = "powl";
157 Names[RTLIB::CEIL_F32] = "ceilf";
158 Names[RTLIB::CEIL_F64] = "ceil";
159 Names[RTLIB::CEIL_F80] = "ceill";
160 Names[RTLIB::CEIL_PPCF128] = "ceill";
161 Names[RTLIB::TRUNC_F32] = "truncf";
162 Names[RTLIB::TRUNC_F64] = "trunc";
163 Names[RTLIB::TRUNC_F80] = "truncl";
164 Names[RTLIB::TRUNC_PPCF128] = "truncl";
165 Names[RTLIB::RINT_F32] = "rintf";
166 Names[RTLIB::RINT_F64] = "rint";
167 Names[RTLIB::RINT_F80] = "rintl";
168 Names[RTLIB::RINT_PPCF128] = "rintl";
169 Names[RTLIB::NEARBYINT_F32] = "nearbyintf";
170 Names[RTLIB::NEARBYINT_F64] = "nearbyint";
171 Names[RTLIB::NEARBYINT_F80] = "nearbyintl";
172 Names[RTLIB::NEARBYINT_PPCF128] = "nearbyintl";
173 Names[RTLIB::FLOOR_F32] = "floorf";
174 Names[RTLIB::FLOOR_F64] = "floor";
175 Names[RTLIB::FLOOR_F80] = "floorl";
176 Names[RTLIB::FLOOR_PPCF128] = "floorl";
177 Names[RTLIB::FPEXT_F32_F64] = "__extendsfdf2";
178 Names[RTLIB::FPEXT_F16_F32] = "__gnu_h2f_ieee";
179 Names[RTLIB::FPROUND_F32_F16] = "__gnu_f2h_ieee";
180 Names[RTLIB::FPROUND_F64_F32] = "__truncdfsf2";
181 Names[RTLIB::FPROUND_F80_F32] = "__truncxfsf2";
182 Names[RTLIB::FPROUND_PPCF128_F32] = "__trunctfsf2";
183 Names[RTLIB::FPROUND_F80_F64] = "__truncxfdf2";
184 Names[RTLIB::FPROUND_PPCF128_F64] = "__trunctfdf2";
185 Names[RTLIB::FPTOSINT_F32_I8] = "__fixsfi8";
186 Names[RTLIB::FPTOSINT_F32_I16] = "__fixsfi16";
187 Names[RTLIB::FPTOSINT_F32_I32] = "__fixsfsi";
188 Names[RTLIB::FPTOSINT_F32_I64] = "__fixsfdi";
189 Names[RTLIB::FPTOSINT_F32_I128] = "__fixsfti";
190 Names[RTLIB::FPTOSINT_F64_I32] = "__fixdfsi";
191 Names[RTLIB::FPTOSINT_F64_I64] = "__fixdfdi";
192 Names[RTLIB::FPTOSINT_F64_I128] = "__fixdfti";
193 Names[RTLIB::FPTOSINT_F80_I32] = "__fixxfsi";
194 Names[RTLIB::FPTOSINT_F80_I64] = "__fixxfdi";
195 Names[RTLIB::FPTOSINT_F80_I128] = "__fixxfti";
196 Names[RTLIB::FPTOSINT_PPCF128_I32] = "__fixtfsi";
197 Names[RTLIB::FPTOSINT_PPCF128_I64] = "__fixtfdi";
198 Names[RTLIB::FPTOSINT_PPCF128_I128] = "__fixtfti";
199 Names[RTLIB::FPTOUINT_F32_I8] = "__fixunssfi8";
200 Names[RTLIB::FPTOUINT_F32_I16] = "__fixunssfi16";
201 Names[RTLIB::FPTOUINT_F32_I32] = "__fixunssfsi";
202 Names[RTLIB::FPTOUINT_F32_I64] = "__fixunssfdi";
203 Names[RTLIB::FPTOUINT_F32_I128] = "__fixunssfti";
204 Names[RTLIB::FPTOUINT_F64_I32] = "__fixunsdfsi";
205 Names[RTLIB::FPTOUINT_F64_I64] = "__fixunsdfdi";
206 Names[RTLIB::FPTOUINT_F64_I128] = "__fixunsdfti";
207 Names[RTLIB::FPTOUINT_F80_I32] = "__fixunsxfsi";
208 Names[RTLIB::FPTOUINT_F80_I64] = "__fixunsxfdi";
209 Names[RTLIB::FPTOUINT_F80_I128] = "__fixunsxfti";
210 Names[RTLIB::FPTOUINT_PPCF128_I32] = "__fixunstfsi";
211 Names[RTLIB::FPTOUINT_PPCF128_I64] = "__fixunstfdi";
212 Names[RTLIB::FPTOUINT_PPCF128_I128] = "__fixunstfti";
213 Names[RTLIB::SINTTOFP_I32_F32] = "__floatsisf";
214 Names[RTLIB::SINTTOFP_I32_F64] = "__floatsidf";
215 Names[RTLIB::SINTTOFP_I32_F80] = "__floatsixf";
216 Names[RTLIB::SINTTOFP_I32_PPCF128] = "__floatsitf";
217 Names[RTLIB::SINTTOFP_I64_F32] = "__floatdisf";
218 Names[RTLIB::SINTTOFP_I64_F64] = "__floatdidf";
219 Names[RTLIB::SINTTOFP_I64_F80] = "__floatdixf";
220 Names[RTLIB::SINTTOFP_I64_PPCF128] = "__floatditf";
221 Names[RTLIB::SINTTOFP_I128_F32] = "__floattisf";
222 Names[RTLIB::SINTTOFP_I128_F64] = "__floattidf";
223 Names[RTLIB::SINTTOFP_I128_F80] = "__floattixf";
224 Names[RTLIB::SINTTOFP_I128_PPCF128] = "__floattitf";
225 Names[RTLIB::UINTTOFP_I32_F32] = "__floatunsisf";
226 Names[RTLIB::UINTTOFP_I32_F64] = "__floatunsidf";
227 Names[RTLIB::UINTTOFP_I32_F80] = "__floatunsixf";
228 Names[RTLIB::UINTTOFP_I32_PPCF128] = "__floatunsitf";
229 Names[RTLIB::UINTTOFP_I64_F32] = "__floatundisf";
230 Names[RTLIB::UINTTOFP_I64_F64] = "__floatundidf";
231 Names[RTLIB::UINTTOFP_I64_F80] = "__floatundixf";
232 Names[RTLIB::UINTTOFP_I64_PPCF128] = "__floatunditf";
233 Names[RTLIB::UINTTOFP_I128_F32] = "__floatuntisf";
234 Names[RTLIB::UINTTOFP_I128_F64] = "__floatuntidf";
235 Names[RTLIB::UINTTOFP_I128_F80] = "__floatuntixf";
236 Names[RTLIB::UINTTOFP_I128_PPCF128] = "__floatuntitf";
237 Names[RTLIB::OEQ_F32] = "__eqsf2";
238 Names[RTLIB::OEQ_F64] = "__eqdf2";
239 Names[RTLIB::UNE_F32] = "__nesf2";
240 Names[RTLIB::UNE_F64] = "__nedf2";
241 Names[RTLIB::OGE_F32] = "__gesf2";
242 Names[RTLIB::OGE_F64] = "__gedf2";
243 Names[RTLIB::OLT_F32] = "__ltsf2";
244 Names[RTLIB::OLT_F64] = "__ltdf2";
245 Names[RTLIB::OLE_F32] = "__lesf2";
246 Names[RTLIB::OLE_F64] = "__ledf2";
247 Names[RTLIB::OGT_F32] = "__gtsf2";
248 Names[RTLIB::OGT_F64] = "__gtdf2";
249 Names[RTLIB::UO_F32] = "__unordsf2";
250 Names[RTLIB::UO_F64] = "__unorddf2";
251 Names[RTLIB::O_F32] = "__unordsf2";
252 Names[RTLIB::O_F64] = "__unorddf2";
253 Names[RTLIB::MEMCPY] = "memcpy";
254 Names[RTLIB::MEMMOVE] = "memmove";
255 Names[RTLIB::MEMSET] = "memset";
256 Names[RTLIB::UNWIND_RESUME] = "_Unwind_Resume";
259 /// InitLibcallCallingConvs - Set default libcall CallingConvs.
261 static void InitLibcallCallingConvs(CallingConv::ID *CCs) {
262 for (int i = 0; i < RTLIB::UNKNOWN_LIBCALL; ++i) {
263 CCs[i] = CallingConv::C;
267 /// getFPEXT - Return the FPEXT_*_* value for the given types, or
268 /// UNKNOWN_LIBCALL if there is none.
269 RTLIB::Libcall RTLIB::getFPEXT(EVT OpVT, EVT RetVT) {
270 if (OpVT == MVT::f32) {
271 if (RetVT == MVT::f64)
272 return FPEXT_F32_F64;
275 return UNKNOWN_LIBCALL;
278 /// getFPROUND - Return the FPROUND_*_* value for the given types, or
279 /// UNKNOWN_LIBCALL if there is none.
280 RTLIB::Libcall RTLIB::getFPROUND(EVT OpVT, EVT RetVT) {
281 if (RetVT == MVT::f32) {
282 if (OpVT == MVT::f64)
283 return FPROUND_F64_F32;
284 if (OpVT == MVT::f80)
285 return FPROUND_F80_F32;
286 if (OpVT == MVT::ppcf128)
287 return FPROUND_PPCF128_F32;
288 } else if (RetVT == MVT::f64) {
289 if (OpVT == MVT::f80)
290 return FPROUND_F80_F64;
291 if (OpVT == MVT::ppcf128)
292 return FPROUND_PPCF128_F64;
295 return UNKNOWN_LIBCALL;
298 /// getFPTOSINT - Return the FPTOSINT_*_* value for the given types, or
299 /// UNKNOWN_LIBCALL if there is none.
300 RTLIB::Libcall RTLIB::getFPTOSINT(EVT OpVT, EVT RetVT) {
301 if (OpVT == MVT::f32) {
302 if (RetVT == MVT::i8)
303 return FPTOSINT_F32_I8;
304 if (RetVT == MVT::i16)
305 return FPTOSINT_F32_I16;
306 if (RetVT == MVT::i32)
307 return FPTOSINT_F32_I32;
308 if (RetVT == MVT::i64)
309 return FPTOSINT_F32_I64;
310 if (RetVT == MVT::i128)
311 return FPTOSINT_F32_I128;
312 } else if (OpVT == MVT::f64) {
313 if (RetVT == MVT::i32)
314 return FPTOSINT_F64_I32;
315 if (RetVT == MVT::i64)
316 return FPTOSINT_F64_I64;
317 if (RetVT == MVT::i128)
318 return FPTOSINT_F64_I128;
319 } else if (OpVT == MVT::f80) {
320 if (RetVT == MVT::i32)
321 return FPTOSINT_F80_I32;
322 if (RetVT == MVT::i64)
323 return FPTOSINT_F80_I64;
324 if (RetVT == MVT::i128)
325 return FPTOSINT_F80_I128;
326 } else if (OpVT == MVT::ppcf128) {
327 if (RetVT == MVT::i32)
328 return FPTOSINT_PPCF128_I32;
329 if (RetVT == MVT::i64)
330 return FPTOSINT_PPCF128_I64;
331 if (RetVT == MVT::i128)
332 return FPTOSINT_PPCF128_I128;
334 return UNKNOWN_LIBCALL;
337 /// getFPTOUINT - Return the FPTOUINT_*_* value for the given types, or
338 /// UNKNOWN_LIBCALL if there is none.
339 RTLIB::Libcall RTLIB::getFPTOUINT(EVT OpVT, EVT RetVT) {
340 if (OpVT == MVT::f32) {
341 if (RetVT == MVT::i8)
342 return FPTOUINT_F32_I8;
343 if (RetVT == MVT::i16)
344 return FPTOUINT_F32_I16;
345 if (RetVT == MVT::i32)
346 return FPTOUINT_F32_I32;
347 if (RetVT == MVT::i64)
348 return FPTOUINT_F32_I64;
349 if (RetVT == MVT::i128)
350 return FPTOUINT_F32_I128;
351 } else if (OpVT == MVT::f64) {
352 if (RetVT == MVT::i32)
353 return FPTOUINT_F64_I32;
354 if (RetVT == MVT::i64)
355 return FPTOUINT_F64_I64;
356 if (RetVT == MVT::i128)
357 return FPTOUINT_F64_I128;
358 } else if (OpVT == MVT::f80) {
359 if (RetVT == MVT::i32)
360 return FPTOUINT_F80_I32;
361 if (RetVT == MVT::i64)
362 return FPTOUINT_F80_I64;
363 if (RetVT == MVT::i128)
364 return FPTOUINT_F80_I128;
365 } else if (OpVT == MVT::ppcf128) {
366 if (RetVT == MVT::i32)
367 return FPTOUINT_PPCF128_I32;
368 if (RetVT == MVT::i64)
369 return FPTOUINT_PPCF128_I64;
370 if (RetVT == MVT::i128)
371 return FPTOUINT_PPCF128_I128;
373 return UNKNOWN_LIBCALL;
376 /// getSINTTOFP - Return the SINTTOFP_*_* value for the given types, or
377 /// UNKNOWN_LIBCALL if there is none.
378 RTLIB::Libcall RTLIB::getSINTTOFP(EVT OpVT, EVT RetVT) {
379 if (OpVT == MVT::i32) {
380 if (RetVT == MVT::f32)
381 return SINTTOFP_I32_F32;
382 else if (RetVT == MVT::f64)
383 return SINTTOFP_I32_F64;
384 else if (RetVT == MVT::f80)
385 return SINTTOFP_I32_F80;
386 else if (RetVT == MVT::ppcf128)
387 return SINTTOFP_I32_PPCF128;
388 } else if (OpVT == MVT::i64) {
389 if (RetVT == MVT::f32)
390 return SINTTOFP_I64_F32;
391 else if (RetVT == MVT::f64)
392 return SINTTOFP_I64_F64;
393 else if (RetVT == MVT::f80)
394 return SINTTOFP_I64_F80;
395 else if (RetVT == MVT::ppcf128)
396 return SINTTOFP_I64_PPCF128;
397 } else if (OpVT == MVT::i128) {
398 if (RetVT == MVT::f32)
399 return SINTTOFP_I128_F32;
400 else if (RetVT == MVT::f64)
401 return SINTTOFP_I128_F64;
402 else if (RetVT == MVT::f80)
403 return SINTTOFP_I128_F80;
404 else if (RetVT == MVT::ppcf128)
405 return SINTTOFP_I128_PPCF128;
407 return UNKNOWN_LIBCALL;
410 /// getUINTTOFP - Return the UINTTOFP_*_* value for the given types, or
411 /// UNKNOWN_LIBCALL if there is none.
412 RTLIB::Libcall RTLIB::getUINTTOFP(EVT OpVT, EVT RetVT) {
413 if (OpVT == MVT::i32) {
414 if (RetVT == MVT::f32)
415 return UINTTOFP_I32_F32;
416 else if (RetVT == MVT::f64)
417 return UINTTOFP_I32_F64;
418 else if (RetVT == MVT::f80)
419 return UINTTOFP_I32_F80;
420 else if (RetVT == MVT::ppcf128)
421 return UINTTOFP_I32_PPCF128;
422 } else if (OpVT == MVT::i64) {
423 if (RetVT == MVT::f32)
424 return UINTTOFP_I64_F32;
425 else if (RetVT == MVT::f64)
426 return UINTTOFP_I64_F64;
427 else if (RetVT == MVT::f80)
428 return UINTTOFP_I64_F80;
429 else if (RetVT == MVT::ppcf128)
430 return UINTTOFP_I64_PPCF128;
431 } else if (OpVT == MVT::i128) {
432 if (RetVT == MVT::f32)
433 return UINTTOFP_I128_F32;
434 else if (RetVT == MVT::f64)
435 return UINTTOFP_I128_F64;
436 else if (RetVT == MVT::f80)
437 return UINTTOFP_I128_F80;
438 else if (RetVT == MVT::ppcf128)
439 return UINTTOFP_I128_PPCF128;
441 return UNKNOWN_LIBCALL;
444 /// InitCmpLibcallCCs - Set default comparison libcall CC.
446 static void InitCmpLibcallCCs(ISD::CondCode *CCs) {
447 memset(CCs, ISD::SETCC_INVALID, sizeof(ISD::CondCode)*RTLIB::UNKNOWN_LIBCALL);
448 CCs[RTLIB::OEQ_F32] = ISD::SETEQ;
449 CCs[RTLIB::OEQ_F64] = ISD::SETEQ;
450 CCs[RTLIB::UNE_F32] = ISD::SETNE;
451 CCs[RTLIB::UNE_F64] = ISD::SETNE;
452 CCs[RTLIB::OGE_F32] = ISD::SETGE;
453 CCs[RTLIB::OGE_F64] = ISD::SETGE;
454 CCs[RTLIB::OLT_F32] = ISD::SETLT;
455 CCs[RTLIB::OLT_F64] = ISD::SETLT;
456 CCs[RTLIB::OLE_F32] = ISD::SETLE;
457 CCs[RTLIB::OLE_F64] = ISD::SETLE;
458 CCs[RTLIB::OGT_F32] = ISD::SETGT;
459 CCs[RTLIB::OGT_F64] = ISD::SETGT;
460 CCs[RTLIB::UO_F32] = ISD::SETNE;
461 CCs[RTLIB::UO_F64] = ISD::SETNE;
462 CCs[RTLIB::O_F32] = ISD::SETEQ;
463 CCs[RTLIB::O_F64] = ISD::SETEQ;
466 /// NOTE: The constructor takes ownership of TLOF.
467 TargetLowering::TargetLowering(TargetMachine &tm,TargetLoweringObjectFile *tlof)
468 : TM(tm), TD(TM.getTargetData()), TLOF(*tlof) {
469 // All operations default to being supported.
470 memset(OpActions, 0, sizeof(OpActions));
471 memset(LoadExtActions, 0, sizeof(LoadExtActions));
472 memset(TruncStoreActions, 0, sizeof(TruncStoreActions));
473 memset(IndexedModeActions, 0, sizeof(IndexedModeActions));
474 memset(ConvertActions, 0, sizeof(ConvertActions));
475 memset(CondCodeActions, 0, sizeof(CondCodeActions));
477 // Set default actions for various operations.
478 for (unsigned VT = 0; VT != (unsigned)MVT::LAST_VALUETYPE; ++VT) {
479 // Default all indexed load / store to expand.
480 for (unsigned IM = (unsigned)ISD::PRE_INC;
481 IM != (unsigned)ISD::LAST_INDEXED_MODE; ++IM) {
482 setIndexedLoadAction(IM, (MVT::SimpleValueType)VT, Expand);
483 setIndexedStoreAction(IM, (MVT::SimpleValueType)VT, Expand);
486 // These operations default to expand.
487 setOperationAction(ISD::FGETSIGN, (MVT::SimpleValueType)VT, Expand);
488 setOperationAction(ISD::CONCAT_VECTORS, (MVT::SimpleValueType)VT, Expand);
491 // Most targets ignore the @llvm.prefetch intrinsic.
492 setOperationAction(ISD::PREFETCH, MVT::Other, Expand);
494 // ConstantFP nodes default to expand. Targets can either change this to
495 // Legal, in which case all fp constants are legal, or use isFPImmLegal()
496 // to optimize expansions for certain constants.
497 setOperationAction(ISD::ConstantFP, MVT::f32, Expand);
498 setOperationAction(ISD::ConstantFP, MVT::f64, Expand);
499 setOperationAction(ISD::ConstantFP, MVT::f80, Expand);
501 // These library functions default to expand.
502 setOperationAction(ISD::FLOG , MVT::f64, Expand);
503 setOperationAction(ISD::FLOG2, MVT::f64, Expand);
504 setOperationAction(ISD::FLOG10,MVT::f64, Expand);
505 setOperationAction(ISD::FEXP , MVT::f64, Expand);
506 setOperationAction(ISD::FEXP2, MVT::f64, Expand);
507 setOperationAction(ISD::FLOG , MVT::f32, Expand);
508 setOperationAction(ISD::FLOG2, MVT::f32, Expand);
509 setOperationAction(ISD::FLOG10,MVT::f32, Expand);
510 setOperationAction(ISD::FEXP , MVT::f32, Expand);
511 setOperationAction(ISD::FEXP2, MVT::f32, Expand);
513 // Default ISD::TRAP to expand (which turns it into abort).
514 setOperationAction(ISD::TRAP, MVT::Other, Expand);
516 IsLittleEndian = TD->isLittleEndian();
517 ShiftAmountTy = PointerTy = MVT::getIntegerVT(8*TD->getPointerSize());
518 memset(RegClassForVT, 0,MVT::LAST_VALUETYPE*sizeof(TargetRegisterClass*));
519 memset(TargetDAGCombineArray, 0, array_lengthof(TargetDAGCombineArray));
520 maxStoresPerMemset = maxStoresPerMemcpy = maxStoresPerMemmove = 8;
521 benefitFromCodePlacementOpt = false;
522 UseUnderscoreSetJmp = false;
523 UseUnderscoreLongJmp = false;
524 SelectIsExpensive = false;
525 IntDivIsCheap = false;
526 Pow2DivIsCheap = false;
527 StackPointerRegisterToSaveRestore = 0;
528 ExceptionPointerRegister = 0;
529 ExceptionSelectorRegister = 0;
530 BooleanContents = UndefinedBooleanContent;
531 SchedPreferenceInfo = SchedulingForLatency;
533 JumpBufAlignment = 0;
534 IfCvtBlockSizeLimit = 2;
535 IfCvtDupBlockSizeLimit = 0;
536 PrefLoopAlignment = 0;
538 InitLibcallNames(LibcallRoutineNames);
539 InitCmpLibcallCCs(CmpLibcallCCs);
540 InitLibcallCallingConvs(LibcallCallingConvs);
543 TargetLowering::~TargetLowering() {
547 /// canOpTrap - Returns true if the operation can trap for the value type.
548 /// VT must be a legal type.
549 bool TargetLowering::canOpTrap(unsigned Op, EVT VT) const {
550 assert(isTypeLegal(VT));
565 static unsigned getVectorTypeBreakdownMVT(MVT VT, MVT &IntermediateVT,
566 unsigned &NumIntermediates,
568 TargetLowering* TLI) {
569 // Figure out the right, legal destination reg to copy into.
570 unsigned NumElts = VT.getVectorNumElements();
571 MVT EltTy = VT.getVectorElementType();
573 unsigned NumVectorRegs = 1;
575 // FIXME: We don't support non-power-of-2-sized vectors for now. Ideally we
576 // could break down into LHS/RHS like LegalizeDAG does.
577 if (!isPowerOf2_32(NumElts)) {
578 NumVectorRegs = NumElts;
582 // Divide the input until we get to a supported size. This will always
583 // end with a scalar if the target doesn't support vectors.
584 while (NumElts > 1 && !TLI->isTypeLegal(MVT::getVectorVT(EltTy, NumElts))) {
589 NumIntermediates = NumVectorRegs;
591 MVT NewVT = MVT::getVectorVT(EltTy, NumElts);
592 if (!TLI->isTypeLegal(NewVT))
594 IntermediateVT = NewVT;
596 EVT DestVT = TLI->getRegisterType(NewVT);
598 if (EVT(DestVT).bitsLT(NewVT)) {
599 // Value is expanded, e.g. i64 -> i16.
600 return NumVectorRegs*(NewVT.getSizeInBits()/DestVT.getSizeInBits());
602 // Otherwise, promotion or legal types use the same number of registers as
603 // the vector decimated to the appropriate level.
604 return NumVectorRegs;
610 /// computeRegisterProperties - Once all of the register classes are added,
611 /// this allows us to compute derived properties we expose.
612 void TargetLowering::computeRegisterProperties() {
613 assert(MVT::LAST_VALUETYPE <= MVT::MAX_ALLOWED_VALUETYPE &&
614 "Too many value types for ValueTypeActions to hold!");
616 // Everything defaults to needing one register.
617 for (unsigned i = 0; i != MVT::LAST_VALUETYPE; ++i) {
618 NumRegistersForVT[i] = 1;
619 RegisterTypeForVT[i] = TransformToType[i] = (MVT::SimpleValueType)i;
621 // ...except isVoid, which doesn't need any registers.
622 NumRegistersForVT[MVT::isVoid] = 0;
624 // Find the largest integer register class.
625 unsigned LargestIntReg = MVT::LAST_INTEGER_VALUETYPE;
626 for (; RegClassForVT[LargestIntReg] == 0; --LargestIntReg)
627 assert(LargestIntReg != MVT::i1 && "No integer registers defined!");
629 // Every integer value type larger than this largest register takes twice as
630 // many registers to represent as the previous ValueType.
631 for (unsigned ExpandedReg = LargestIntReg + 1; ; ++ExpandedReg) {
632 EVT ExpandedVT = (MVT::SimpleValueType)ExpandedReg;
633 if (!ExpandedVT.isInteger())
635 NumRegistersForVT[ExpandedReg] = 2*NumRegistersForVT[ExpandedReg-1];
636 RegisterTypeForVT[ExpandedReg] = (MVT::SimpleValueType)LargestIntReg;
637 TransformToType[ExpandedReg] = (MVT::SimpleValueType)(ExpandedReg - 1);
638 ValueTypeActions.setTypeAction(ExpandedVT, Expand);
641 // Inspect all of the ValueType's smaller than the largest integer
642 // register to see which ones need promotion.
643 unsigned LegalIntReg = LargestIntReg;
644 for (unsigned IntReg = LargestIntReg - 1;
645 IntReg >= (unsigned)MVT::i1; --IntReg) {
646 EVT IVT = (MVT::SimpleValueType)IntReg;
647 if (isTypeLegal(IVT)) {
648 LegalIntReg = IntReg;
650 RegisterTypeForVT[IntReg] = TransformToType[IntReg] =
651 (MVT::SimpleValueType)LegalIntReg;
652 ValueTypeActions.setTypeAction(IVT, Promote);
656 // ppcf128 type is really two f64's.
657 if (!isTypeLegal(MVT::ppcf128)) {
658 NumRegistersForVT[MVT::ppcf128] = 2*NumRegistersForVT[MVT::f64];
659 RegisterTypeForVT[MVT::ppcf128] = MVT::f64;
660 TransformToType[MVT::ppcf128] = MVT::f64;
661 ValueTypeActions.setTypeAction(MVT::ppcf128, Expand);
664 // Decide how to handle f64. If the target does not have native f64 support,
665 // expand it to i64 and we will be generating soft float library calls.
666 if (!isTypeLegal(MVT::f64)) {
667 NumRegistersForVT[MVT::f64] = NumRegistersForVT[MVT::i64];
668 RegisterTypeForVT[MVT::f64] = RegisterTypeForVT[MVT::i64];
669 TransformToType[MVT::f64] = MVT::i64;
670 ValueTypeActions.setTypeAction(MVT::f64, Expand);
673 // Decide how to handle f32. If the target does not have native support for
674 // f32, promote it to f64 if it is legal. Otherwise, expand it to i32.
675 if (!isTypeLegal(MVT::f32)) {
676 if (isTypeLegal(MVT::f64)) {
677 NumRegistersForVT[MVT::f32] = NumRegistersForVT[MVT::f64];
678 RegisterTypeForVT[MVT::f32] = RegisterTypeForVT[MVT::f64];
679 TransformToType[MVT::f32] = MVT::f64;
680 ValueTypeActions.setTypeAction(MVT::f32, Promote);
682 NumRegistersForVT[MVT::f32] = NumRegistersForVT[MVT::i32];
683 RegisterTypeForVT[MVT::f32] = RegisterTypeForVT[MVT::i32];
684 TransformToType[MVT::f32] = MVT::i32;
685 ValueTypeActions.setTypeAction(MVT::f32, Expand);
689 // Loop over all of the vector value types to see which need transformations.
690 for (unsigned i = MVT::FIRST_VECTOR_VALUETYPE;
691 i <= (unsigned)MVT::LAST_VECTOR_VALUETYPE; ++i) {
692 MVT VT = (MVT::SimpleValueType)i;
693 if (!isTypeLegal(VT)) {
696 unsigned NumIntermediates;
697 NumRegistersForVT[i] =
698 getVectorTypeBreakdownMVT(VT, IntermediateVT, NumIntermediates,
700 RegisterTypeForVT[i] = RegisterVT;
702 // Determine if there is a legal wider type.
703 bool IsLegalWiderType = false;
704 EVT EltVT = VT.getVectorElementType();
705 unsigned NElts = VT.getVectorNumElements();
706 for (unsigned nVT = i+1; nVT <= MVT::LAST_VECTOR_VALUETYPE; ++nVT) {
707 EVT SVT = (MVT::SimpleValueType)nVT;
708 if (isTypeLegal(SVT) && SVT.getVectorElementType() == EltVT &&
709 SVT.getVectorNumElements() > NElts && NElts != 1) {
710 TransformToType[i] = SVT;
711 ValueTypeActions.setTypeAction(VT, Promote);
712 IsLegalWiderType = true;
716 if (!IsLegalWiderType) {
717 EVT NVT = VT.getPow2VectorType();
719 // Type is already a power of 2. The default action is to split.
720 TransformToType[i] = MVT::Other;
721 ValueTypeActions.setTypeAction(VT, Expand);
723 TransformToType[i] = NVT;
724 ValueTypeActions.setTypeAction(VT, Promote);
731 const char *TargetLowering::getTargetNodeName(unsigned Opcode) const {
736 MVT::SimpleValueType TargetLowering::getSetCCResultType(EVT VT) const {
737 return PointerTy.SimpleTy;
740 MVT::SimpleValueType TargetLowering::getCmpLibcallReturnType() const {
741 return MVT::i32; // return the default value
744 /// getVectorTypeBreakdown - Vector types are broken down into some number of
745 /// legal first class types. For example, MVT::v8f32 maps to 2 MVT::v4f32
746 /// with Altivec or SSE1, or 8 promoted MVT::f64 values with the X86 FP stack.
747 /// Similarly, MVT::v2i64 turns into 4 MVT::i32 values with both PPC and X86.
749 /// This method returns the number of registers needed, and the VT for each
750 /// register. It also returns the VT and quantity of the intermediate values
751 /// before they are promoted/expanded.
753 unsigned TargetLowering::getVectorTypeBreakdown(LLVMContext &Context, EVT VT,
755 unsigned &NumIntermediates,
756 EVT &RegisterVT) const {
757 // Figure out the right, legal destination reg to copy into.
758 unsigned NumElts = VT.getVectorNumElements();
759 EVT EltTy = VT.getVectorElementType();
761 unsigned NumVectorRegs = 1;
763 // FIXME: We don't support non-power-of-2-sized vectors for now. Ideally we
764 // could break down into LHS/RHS like LegalizeDAG does.
765 if (!isPowerOf2_32(NumElts)) {
766 NumVectorRegs = NumElts;
770 // Divide the input until we get to a supported size. This will always
771 // end with a scalar if the target doesn't support vectors.
772 while (NumElts > 1 && !isTypeLegal(
773 EVT::getVectorVT(Context, EltTy, NumElts))) {
778 NumIntermediates = NumVectorRegs;
780 EVT NewVT = EVT::getVectorVT(Context, EltTy, NumElts);
781 if (!isTypeLegal(NewVT))
783 IntermediateVT = NewVT;
785 EVT DestVT = getRegisterType(Context, NewVT);
787 if (DestVT.bitsLT(NewVT)) {
788 // Value is expanded, e.g. i64 -> i16.
789 return NumVectorRegs*(NewVT.getSizeInBits()/DestVT.getSizeInBits());
791 // Otherwise, promotion or legal types use the same number of registers as
792 // the vector decimated to the appropriate level.
793 return NumVectorRegs;
799 /// getByValTypeAlignment - Return the desired alignment for ByVal aggregate
800 /// function arguments in the caller parameter area. This is the actual
801 /// alignment, not its logarithm.
802 unsigned TargetLowering::getByValTypeAlignment(const Type *Ty) const {
803 return TD->getCallFrameTypeAlignment(Ty);
806 /// getJumpTableEncoding - Return the entry encoding for a jump table in the
807 /// current function. The returned value is a member of the
808 /// MachineJumpTableInfo::JTEntryKind enum.
809 unsigned TargetLowering::getJumpTableEncoding() const {
810 // In non-pic modes, just use the address of a block.
811 if (getTargetMachine().getRelocationModel() != Reloc::PIC_)
812 return MachineJumpTableInfo::EK_BlockAddress;
814 // In PIC mode, if the target supports a GPRel32 directive, use it.
815 if (getTargetMachine().getMCAsmInfo()->getGPRel32Directive() != 0)
816 return MachineJumpTableInfo::EK_GPRel32BlockAddress;
818 // Otherwise, use a label difference.
819 return MachineJumpTableInfo::EK_LabelDifference32;
822 SDValue TargetLowering::getPICJumpTableRelocBase(SDValue Table,
823 SelectionDAG &DAG) const {
824 // If our PIC model is GP relative, use the global offset table as the base.
825 if (getJumpTableEncoding() == MachineJumpTableInfo::EK_GPRel32BlockAddress)
826 return DAG.getGLOBAL_OFFSET_TABLE(getPointerTy());
830 /// getPICJumpTableRelocBaseExpr - This returns the relocation base for the
831 /// given PIC jumptable, the same as getPICJumpTableRelocBase, but as an
834 TargetLowering::getPICJumpTableRelocBaseExpr(const MachineFunction *MF,
835 unsigned JTI,MCContext &Ctx) const{
836 // The normal PIC reloc base is the label at the start of the jump table.
837 return MCSymbolRefExpr::Create(MF->getJTISymbol(JTI, Ctx), Ctx);
841 TargetLowering::isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const {
842 // Assume that everything is safe in static mode.
843 if (getTargetMachine().getRelocationModel() == Reloc::Static)
846 // In dynamic-no-pic mode, assume that known defined values are safe.
847 if (getTargetMachine().getRelocationModel() == Reloc::DynamicNoPIC &&
849 !GA->getGlobal()->isDeclaration() &&
850 !GA->getGlobal()->isWeakForLinker())
853 // Otherwise assume nothing is safe.
857 //===----------------------------------------------------------------------===//
858 // Optimization Methods
859 //===----------------------------------------------------------------------===//
861 /// ShrinkDemandedConstant - Check to see if the specified operand of the
862 /// specified instruction is a constant integer. If so, check to see if there
863 /// are any bits set in the constant that are not demanded. If so, shrink the
864 /// constant and return true.
865 bool TargetLowering::TargetLoweringOpt::ShrinkDemandedConstant(SDValue Op,
866 const APInt &Demanded) {
867 DebugLoc dl = Op.getDebugLoc();
869 // FIXME: ISD::SELECT, ISD::SELECT_CC
870 switch (Op.getOpcode()) {
875 ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op.getOperand(1));
876 if (!C) return false;
878 if (Op.getOpcode() == ISD::XOR &&
879 (C->getAPIntValue() | (~Demanded)).isAllOnesValue())
882 // if we can expand it to have all bits set, do it
883 if (C->getAPIntValue().intersects(~Demanded)) {
884 EVT VT = Op.getValueType();
885 SDValue New = DAG.getNode(Op.getOpcode(), dl, VT, Op.getOperand(0),
886 DAG.getConstant(Demanded &
889 return CombineTo(Op, New);
899 /// ShrinkDemandedOp - Convert x+y to (VT)((SmallVT)x+(SmallVT)y) if the
900 /// casts are free. This uses isZExtFree and ZERO_EXTEND for the widening
901 /// cast, but it could be generalized for targets with other types of
902 /// implicit widening casts.
904 TargetLowering::TargetLoweringOpt::ShrinkDemandedOp(SDValue Op,
906 const APInt &Demanded,
908 assert(Op.getNumOperands() == 2 &&
909 "ShrinkDemandedOp only supports binary operators!");
910 assert(Op.getNode()->getNumValues() == 1 &&
911 "ShrinkDemandedOp only supports nodes with one result!");
913 // Don't do this if the node has another user, which may require the
915 if (!Op.getNode()->hasOneUse())
918 // Search for the smallest integer type with free casts to and from
919 // Op's type. For expedience, just check power-of-2 integer types.
920 const TargetLowering &TLI = DAG.getTargetLoweringInfo();
921 unsigned SmallVTBits = BitWidth - Demanded.countLeadingZeros();
922 if (!isPowerOf2_32(SmallVTBits))
923 SmallVTBits = NextPowerOf2(SmallVTBits);
924 for (; SmallVTBits < BitWidth; SmallVTBits = NextPowerOf2(SmallVTBits)) {
925 EVT SmallVT = EVT::getIntegerVT(*DAG.getContext(), SmallVTBits);
926 if (TLI.isTruncateFree(Op.getValueType(), SmallVT) &&
927 TLI.isZExtFree(SmallVT, Op.getValueType())) {
928 // We found a type with free casts.
929 SDValue X = DAG.getNode(Op.getOpcode(), dl, SmallVT,
930 DAG.getNode(ISD::TRUNCATE, dl, SmallVT,
931 Op.getNode()->getOperand(0)),
932 DAG.getNode(ISD::TRUNCATE, dl, SmallVT,
933 Op.getNode()->getOperand(1)));
934 SDValue Z = DAG.getNode(ISD::ZERO_EXTEND, dl, Op.getValueType(), X);
935 return CombineTo(Op, Z);
941 /// SimplifyDemandedBits - Look at Op. At this point, we know that only the
942 /// DemandedMask bits of the result of Op are ever used downstream. If we can
943 /// use this information to simplify Op, create a new simplified DAG node and
944 /// return true, returning the original and new nodes in Old and New. Otherwise,
945 /// analyze the expression and return a mask of KnownOne and KnownZero bits for
946 /// the expression (used to simplify the caller). The KnownZero/One bits may
947 /// only be accurate for those bits in the DemandedMask.
948 bool TargetLowering::SimplifyDemandedBits(SDValue Op,
949 const APInt &DemandedMask,
952 TargetLoweringOpt &TLO,
953 unsigned Depth) const {
954 unsigned BitWidth = DemandedMask.getBitWidth();
955 assert(Op.getValueType().getScalarType().getSizeInBits() == BitWidth &&
956 "Mask size mismatches value type size!");
957 APInt NewMask = DemandedMask;
958 DebugLoc dl = Op.getDebugLoc();
960 // Don't know anything.
961 KnownZero = KnownOne = APInt(BitWidth, 0);
963 // Other users may use these bits.
964 if (!Op.getNode()->hasOneUse()) {
966 // If not at the root, Just compute the KnownZero/KnownOne bits to
967 // simplify things downstream.
968 TLO.DAG.ComputeMaskedBits(Op, DemandedMask, KnownZero, KnownOne, Depth);
971 // If this is the root being simplified, allow it to have multiple uses,
972 // just set the NewMask to all bits.
973 NewMask = APInt::getAllOnesValue(BitWidth);
974 } else if (DemandedMask == 0) {
975 // Not demanding any bits from Op.
976 if (Op.getOpcode() != ISD::UNDEF)
977 return TLO.CombineTo(Op, TLO.DAG.getUNDEF(Op.getValueType()));
979 } else if (Depth == 6) { // Limit search depth.
983 APInt KnownZero2, KnownOne2, KnownZeroOut, KnownOneOut;
984 switch (Op.getOpcode()) {
986 // We know all of the bits for a constant!
987 KnownOne = cast<ConstantSDNode>(Op)->getAPIntValue() & NewMask;
988 KnownZero = ~KnownOne & NewMask;
989 return false; // Don't fall through, will infinitely loop.
991 // If the RHS is a constant, check to see if the LHS would be zero without
992 // using the bits from the RHS. Below, we use knowledge about the RHS to
993 // simplify the LHS, here we're using information from the LHS to simplify
995 if (ConstantSDNode *RHSC = dyn_cast<ConstantSDNode>(Op.getOperand(1))) {
996 APInt LHSZero, LHSOne;
997 TLO.DAG.ComputeMaskedBits(Op.getOperand(0), NewMask,
998 LHSZero, LHSOne, Depth+1);
999 // If the LHS already has zeros where RHSC does, this and is dead.
1000 if ((LHSZero & NewMask) == (~RHSC->getAPIntValue() & NewMask))
1001 return TLO.CombineTo(Op, Op.getOperand(0));
1002 // If any of the set bits in the RHS are known zero on the LHS, shrink
1004 if (TLO.ShrinkDemandedConstant(Op, ~LHSZero & NewMask))
1008 if (SimplifyDemandedBits(Op.getOperand(1), NewMask, KnownZero,
1009 KnownOne, TLO, Depth+1))
1011 assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
1012 if (SimplifyDemandedBits(Op.getOperand(0), ~KnownZero & NewMask,
1013 KnownZero2, KnownOne2, TLO, Depth+1))
1015 assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
1017 // If all of the demanded bits are known one on one side, return the other.
1018 // These bits cannot contribute to the result of the 'and'.
1019 if ((NewMask & ~KnownZero2 & KnownOne) == (~KnownZero2 & NewMask))
1020 return TLO.CombineTo(Op, Op.getOperand(0));
1021 if ((NewMask & ~KnownZero & KnownOne2) == (~KnownZero & NewMask))
1022 return TLO.CombineTo(Op, Op.getOperand(1));
1023 // If all of the demanded bits in the inputs are known zeros, return zero.
1024 if ((NewMask & (KnownZero|KnownZero2)) == NewMask)
1025 return TLO.CombineTo(Op, TLO.DAG.getConstant(0, Op.getValueType()));
1026 // If the RHS is a constant, see if we can simplify it.
1027 if (TLO.ShrinkDemandedConstant(Op, ~KnownZero2 & NewMask))
1029 // If the operation can be done in a smaller type, do so.
1030 if (TLO.ShrinkOps && TLO.ShrinkDemandedOp(Op, BitWidth, NewMask, dl))
1033 // Output known-1 bits are only known if set in both the LHS & RHS.
1034 KnownOne &= KnownOne2;
1035 // Output known-0 are known to be clear if zero in either the LHS | RHS.
1036 KnownZero |= KnownZero2;
1039 if (SimplifyDemandedBits(Op.getOperand(1), NewMask, KnownZero,
1040 KnownOne, TLO, Depth+1))
1042 assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
1043 if (SimplifyDemandedBits(Op.getOperand(0), ~KnownOne & NewMask,
1044 KnownZero2, KnownOne2, TLO, Depth+1))
1046 assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
1048 // If all of the demanded bits are known zero on one side, return the other.
1049 // These bits cannot contribute to the result of the 'or'.
1050 if ((NewMask & ~KnownOne2 & KnownZero) == (~KnownOne2 & NewMask))
1051 return TLO.CombineTo(Op, Op.getOperand(0));
1052 if ((NewMask & ~KnownOne & KnownZero2) == (~KnownOne & NewMask))
1053 return TLO.CombineTo(Op, Op.getOperand(1));
1054 // If all of the potentially set bits on one side are known to be set on
1055 // the other side, just use the 'other' side.
1056 if ((NewMask & ~KnownZero & KnownOne2) == (~KnownZero & NewMask))
1057 return TLO.CombineTo(Op, Op.getOperand(0));
1058 if ((NewMask & ~KnownZero2 & KnownOne) == (~KnownZero2 & NewMask))
1059 return TLO.CombineTo(Op, Op.getOperand(1));
1060 // If the RHS is a constant, see if we can simplify it.
1061 if (TLO.ShrinkDemandedConstant(Op, NewMask))
1063 // If the operation can be done in a smaller type, do so.
1064 if (TLO.ShrinkOps && TLO.ShrinkDemandedOp(Op, BitWidth, NewMask, dl))
1067 // Output known-0 bits are only known if clear in both the LHS & RHS.
1068 KnownZero &= KnownZero2;
1069 // Output known-1 are known to be set if set in either the LHS | RHS.
1070 KnownOne |= KnownOne2;
1073 if (SimplifyDemandedBits(Op.getOperand(1), NewMask, KnownZero,
1074 KnownOne, TLO, Depth+1))
1076 assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
1077 if (SimplifyDemandedBits(Op.getOperand(0), NewMask, KnownZero2,
1078 KnownOne2, TLO, Depth+1))
1080 assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
1082 // If all of the demanded bits are known zero on one side, return the other.
1083 // These bits cannot contribute to the result of the 'xor'.
1084 if ((KnownZero & NewMask) == NewMask)
1085 return TLO.CombineTo(Op, Op.getOperand(0));
1086 if ((KnownZero2 & NewMask) == NewMask)
1087 return TLO.CombineTo(Op, Op.getOperand(1));
1088 // If the operation can be done in a smaller type, do so.
1089 if (TLO.ShrinkOps && TLO.ShrinkDemandedOp(Op, BitWidth, NewMask, dl))
1092 // If all of the unknown bits are known to be zero on one side or the other
1093 // (but not both) turn this into an *inclusive* or.
1094 // e.g. (A & C1)^(B & C2) -> (A & C1)|(B & C2) iff C1&C2 == 0
1095 if ((NewMask & ~KnownZero & ~KnownZero2) == 0)
1096 return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::OR, dl, Op.getValueType(),
1100 // Output known-0 bits are known if clear or set in both the LHS & RHS.
1101 KnownZeroOut = (KnownZero & KnownZero2) | (KnownOne & KnownOne2);
1102 // Output known-1 are known to be set if set in only one of the LHS, RHS.
1103 KnownOneOut = (KnownZero & KnownOne2) | (KnownOne & KnownZero2);
1105 // If all of the demanded bits on one side are known, and all of the set
1106 // bits on that side are also known to be set on the other side, turn this
1107 // into an AND, as we know the bits will be cleared.
1108 // e.g. (X | C1) ^ C2 --> (X | C1) & ~C2 iff (C1&C2) == C2
1109 if ((NewMask & (KnownZero|KnownOne)) == NewMask) { // all known
1110 if ((KnownOne & KnownOne2) == KnownOne) {
1111 EVT VT = Op.getValueType();
1112 SDValue ANDC = TLO.DAG.getConstant(~KnownOne & NewMask, VT);
1113 return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::AND, dl, VT,
1114 Op.getOperand(0), ANDC));
1118 // If the RHS is a constant, see if we can simplify it.
1119 // for XOR, we prefer to force bits to 1 if they will make a -1.
1120 // if we can't force bits, try to shrink constant
1121 if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op.getOperand(1))) {
1122 APInt Expanded = C->getAPIntValue() | (~NewMask);
1123 // if we can expand it to have all bits set, do it
1124 if (Expanded.isAllOnesValue()) {
1125 if (Expanded != C->getAPIntValue()) {
1126 EVT VT = Op.getValueType();
1127 SDValue New = TLO.DAG.getNode(Op.getOpcode(), dl,VT, Op.getOperand(0),
1128 TLO.DAG.getConstant(Expanded, VT));
1129 return TLO.CombineTo(Op, New);
1131 // if it already has all the bits set, nothing to change
1132 // but don't shrink either!
1133 } else if (TLO.ShrinkDemandedConstant(Op, NewMask)) {
1138 KnownZero = KnownZeroOut;
1139 KnownOne = KnownOneOut;
1142 if (SimplifyDemandedBits(Op.getOperand(2), NewMask, KnownZero,
1143 KnownOne, TLO, Depth+1))
1145 if (SimplifyDemandedBits(Op.getOperand(1), NewMask, KnownZero2,
1146 KnownOne2, TLO, Depth+1))
1148 assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
1149 assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
1151 // If the operands are constants, see if we can simplify them.
1152 if (TLO.ShrinkDemandedConstant(Op, NewMask))
1155 // Only known if known in both the LHS and RHS.
1156 KnownOne &= KnownOne2;
1157 KnownZero &= KnownZero2;
1159 case ISD::SELECT_CC:
1160 if (SimplifyDemandedBits(Op.getOperand(3), NewMask, KnownZero,
1161 KnownOne, TLO, Depth+1))
1163 if (SimplifyDemandedBits(Op.getOperand(2), NewMask, KnownZero2,
1164 KnownOne2, TLO, Depth+1))
1166 assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
1167 assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
1169 // If the operands are constants, see if we can simplify them.
1170 if (TLO.ShrinkDemandedConstant(Op, NewMask))
1173 // Only known if known in both the LHS and RHS.
1174 KnownOne &= KnownOne2;
1175 KnownZero &= KnownZero2;
1178 if (ConstantSDNode *SA = dyn_cast<ConstantSDNode>(Op.getOperand(1))) {
1179 unsigned ShAmt = SA->getZExtValue();
1180 SDValue InOp = Op.getOperand(0);
1182 // If the shift count is an invalid immediate, don't do anything.
1183 if (ShAmt >= BitWidth)
1186 // If this is ((X >>u C1) << ShAmt), see if we can simplify this into a
1187 // single shift. We can do this if the bottom bits (which are shifted
1188 // out) are never demanded.
1189 if (InOp.getOpcode() == ISD::SRL &&
1190 isa<ConstantSDNode>(InOp.getOperand(1))) {
1191 if (ShAmt && (NewMask & APInt::getLowBitsSet(BitWidth, ShAmt)) == 0) {
1192 unsigned C1= cast<ConstantSDNode>(InOp.getOperand(1))->getZExtValue();
1193 unsigned Opc = ISD::SHL;
1194 int Diff = ShAmt-C1;
1201 TLO.DAG.getConstant(Diff, Op.getOperand(1).getValueType());
1202 EVT VT = Op.getValueType();
1203 return TLO.CombineTo(Op, TLO.DAG.getNode(Opc, dl, VT,
1204 InOp.getOperand(0), NewSA));
1208 if (SimplifyDemandedBits(Op.getOperand(0), NewMask.lshr(ShAmt),
1209 KnownZero, KnownOne, TLO, Depth+1))
1211 KnownZero <<= SA->getZExtValue();
1212 KnownOne <<= SA->getZExtValue();
1213 // low bits known zero.
1214 KnownZero |= APInt::getLowBitsSet(BitWidth, SA->getZExtValue());
1218 if (ConstantSDNode *SA = dyn_cast<ConstantSDNode>(Op.getOperand(1))) {
1219 EVT VT = Op.getValueType();
1220 unsigned ShAmt = SA->getZExtValue();
1221 unsigned VTSize = VT.getSizeInBits();
1222 SDValue InOp = Op.getOperand(0);
1224 // If the shift count is an invalid immediate, don't do anything.
1225 if (ShAmt >= BitWidth)
1228 // If this is ((X << C1) >>u ShAmt), see if we can simplify this into a
1229 // single shift. We can do this if the top bits (which are shifted out)
1230 // are never demanded.
1231 if (InOp.getOpcode() == ISD::SHL &&
1232 isa<ConstantSDNode>(InOp.getOperand(1))) {
1233 if (ShAmt && (NewMask & APInt::getHighBitsSet(VTSize, ShAmt)) == 0) {
1234 unsigned C1= cast<ConstantSDNode>(InOp.getOperand(1))->getZExtValue();
1235 unsigned Opc = ISD::SRL;
1236 int Diff = ShAmt-C1;
1243 TLO.DAG.getConstant(Diff, Op.getOperand(1).getValueType());
1244 return TLO.CombineTo(Op, TLO.DAG.getNode(Opc, dl, VT,
1245 InOp.getOperand(0), NewSA));
1249 // Compute the new bits that are at the top now.
1250 if (SimplifyDemandedBits(InOp, (NewMask << ShAmt),
1251 KnownZero, KnownOne, TLO, Depth+1))
1253 assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
1254 KnownZero = KnownZero.lshr(ShAmt);
1255 KnownOne = KnownOne.lshr(ShAmt);
1257 APInt HighBits = APInt::getHighBitsSet(BitWidth, ShAmt);
1258 KnownZero |= HighBits; // High bits known zero.
1262 // If this is an arithmetic shift right and only the low-bit is set, we can
1263 // always convert this into a logical shr, even if the shift amount is
1264 // variable. The low bit of the shift cannot be an input sign bit unless
1265 // the shift amount is >= the size of the datatype, which is undefined.
1266 if (DemandedMask == 1)
1267 return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::SRL, dl, Op.getValueType(),
1268 Op.getOperand(0), Op.getOperand(1)));
1270 if (ConstantSDNode *SA = dyn_cast<ConstantSDNode>(Op.getOperand(1))) {
1271 EVT VT = Op.getValueType();
1272 unsigned ShAmt = SA->getZExtValue();
1274 // If the shift count is an invalid immediate, don't do anything.
1275 if (ShAmt >= BitWidth)
1278 APInt InDemandedMask = (NewMask << ShAmt);
1280 // If any of the demanded bits are produced by the sign extension, we also
1281 // demand the input sign bit.
1282 APInt HighBits = APInt::getHighBitsSet(BitWidth, ShAmt);
1283 if (HighBits.intersects(NewMask))
1284 InDemandedMask |= APInt::getSignBit(VT.getScalarType().getSizeInBits());
1286 if (SimplifyDemandedBits(Op.getOperand(0), InDemandedMask,
1287 KnownZero, KnownOne, TLO, Depth+1))
1289 assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
1290 KnownZero = KnownZero.lshr(ShAmt);
1291 KnownOne = KnownOne.lshr(ShAmt);
1293 // Handle the sign bit, adjusted to where it is now in the mask.
1294 APInt SignBit = APInt::getSignBit(BitWidth).lshr(ShAmt);
1296 // If the input sign bit is known to be zero, or if none of the top bits
1297 // are demanded, turn this into an unsigned shift right.
1298 if (KnownZero.intersects(SignBit) || (HighBits & ~NewMask) == HighBits) {
1299 return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::SRL, dl, VT,
1302 } else if (KnownOne.intersects(SignBit)) { // New bits are known one.
1303 KnownOne |= HighBits;
1307 case ISD::SIGN_EXTEND_INREG: {
1308 EVT EVT = cast<VTSDNode>(Op.getOperand(1))->getVT();
1310 // Sign extension. Compute the demanded bits in the result that are not
1311 // present in the input.
1313 APInt::getHighBitsSet(BitWidth,
1314 BitWidth - EVT.getScalarType().getSizeInBits()) &
1317 // If none of the extended bits are demanded, eliminate the sextinreg.
1319 return TLO.CombineTo(Op, Op.getOperand(0));
1321 APInt InSignBit = APInt::getSignBit(EVT.getScalarType().getSizeInBits());
1322 InSignBit.zext(BitWidth);
1323 APInt InputDemandedBits =
1324 APInt::getLowBitsSet(BitWidth,
1325 EVT.getScalarType().getSizeInBits()) &
1328 // Since the sign extended bits are demanded, we know that the sign
1330 InputDemandedBits |= InSignBit;
1332 if (SimplifyDemandedBits(Op.getOperand(0), InputDemandedBits,
1333 KnownZero, KnownOne, TLO, Depth+1))
1335 assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
1337 // If the sign bit of the input is known set or clear, then we know the
1338 // top bits of the result.
1340 // If the input sign bit is known zero, convert this into a zero extension.
1341 if (KnownZero.intersects(InSignBit))
1342 return TLO.CombineTo(Op,
1343 TLO.DAG.getZeroExtendInReg(Op.getOperand(0),dl,EVT));
1345 if (KnownOne.intersects(InSignBit)) { // Input sign bit known set
1346 KnownOne |= NewBits;
1347 KnownZero &= ~NewBits;
1348 } else { // Input sign bit unknown
1349 KnownZero &= ~NewBits;
1350 KnownOne &= ~NewBits;
1354 case ISD::ZERO_EXTEND: {
1355 unsigned OperandBitWidth =
1356 Op.getOperand(0).getValueType().getScalarType().getSizeInBits();
1357 APInt InMask = NewMask;
1358 InMask.trunc(OperandBitWidth);
1360 // If none of the top bits are demanded, convert this into an any_extend.
1362 APInt::getHighBitsSet(BitWidth, BitWidth - OperandBitWidth) & NewMask;
1363 if (!NewBits.intersects(NewMask))
1364 return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::ANY_EXTEND, dl,
1368 if (SimplifyDemandedBits(Op.getOperand(0), InMask,
1369 KnownZero, KnownOne, TLO, Depth+1))
1371 assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
1372 KnownZero.zext(BitWidth);
1373 KnownOne.zext(BitWidth);
1374 KnownZero |= NewBits;
1377 case ISD::SIGN_EXTEND: {
1378 EVT InVT = Op.getOperand(0).getValueType();
1379 unsigned InBits = InVT.getScalarType().getSizeInBits();
1380 APInt InMask = APInt::getLowBitsSet(BitWidth, InBits);
1381 APInt InSignBit = APInt::getBitsSet(BitWidth, InBits - 1, InBits);
1382 APInt NewBits = ~InMask & NewMask;
1384 // If none of the top bits are demanded, convert this into an any_extend.
1386 return TLO.CombineTo(Op,TLO.DAG.getNode(ISD::ANY_EXTEND, dl,
1390 // Since some of the sign extended bits are demanded, we know that the sign
1392 APInt InDemandedBits = InMask & NewMask;
1393 InDemandedBits |= InSignBit;
1394 InDemandedBits.trunc(InBits);
1396 if (SimplifyDemandedBits(Op.getOperand(0), InDemandedBits, KnownZero,
1397 KnownOne, TLO, Depth+1))
1399 KnownZero.zext(BitWidth);
1400 KnownOne.zext(BitWidth);
1402 // If the sign bit is known zero, convert this to a zero extend.
1403 if (KnownZero.intersects(InSignBit))
1404 return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::ZERO_EXTEND, dl,
1408 // If the sign bit is known one, the top bits match.
1409 if (KnownOne.intersects(InSignBit)) {
1410 KnownOne |= NewBits;
1411 KnownZero &= ~NewBits;
1412 } else { // Otherwise, top bits aren't known.
1413 KnownOne &= ~NewBits;
1414 KnownZero &= ~NewBits;
1418 case ISD::ANY_EXTEND: {
1419 unsigned OperandBitWidth =
1420 Op.getOperand(0).getValueType().getScalarType().getSizeInBits();
1421 APInt InMask = NewMask;
1422 InMask.trunc(OperandBitWidth);
1423 if (SimplifyDemandedBits(Op.getOperand(0), InMask,
1424 KnownZero, KnownOne, TLO, Depth+1))
1426 assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
1427 KnownZero.zext(BitWidth);
1428 KnownOne.zext(BitWidth);
1431 case ISD::TRUNCATE: {
1432 // Simplify the input, using demanded bit information, and compute the known
1433 // zero/one bits live out.
1434 unsigned OperandBitWidth =
1435 Op.getOperand(0).getValueType().getScalarType().getSizeInBits();
1436 APInt TruncMask = NewMask;
1437 TruncMask.zext(OperandBitWidth);
1438 if (SimplifyDemandedBits(Op.getOperand(0), TruncMask,
1439 KnownZero, KnownOne, TLO, Depth+1))
1441 KnownZero.trunc(BitWidth);
1442 KnownOne.trunc(BitWidth);
1444 // If the input is only used by this truncate, see if we can shrink it based
1445 // on the known demanded bits.
1446 if (Op.getOperand(0).getNode()->hasOneUse()) {
1447 SDValue In = Op.getOperand(0);
1448 switch (In.getOpcode()) {
1451 // Shrink SRL by a constant if none of the high bits shifted in are
1453 if (ConstantSDNode *ShAmt = dyn_cast<ConstantSDNode>(In.getOperand(1))){
1454 APInt HighBits = APInt::getHighBitsSet(OperandBitWidth,
1455 OperandBitWidth - BitWidth);
1456 HighBits = HighBits.lshr(ShAmt->getZExtValue());
1457 HighBits.trunc(BitWidth);
1459 if (ShAmt->getZExtValue() < BitWidth && !(HighBits & NewMask)) {
1460 // None of the shifted in bits are needed. Add a truncate of the
1461 // shift input, then shift it.
1462 SDValue NewTrunc = TLO.DAG.getNode(ISD::TRUNCATE, dl,
1465 return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::SRL, dl,
1475 assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
1478 case ISD::AssertZext: {
1479 EVT VT = cast<VTSDNode>(Op.getOperand(1))->getVT();
1480 APInt InMask = APInt::getLowBitsSet(BitWidth,
1481 VT.getSizeInBits());
1482 if (SimplifyDemandedBits(Op.getOperand(0), InMask & NewMask,
1483 KnownZero, KnownOne, TLO, Depth+1))
1485 assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
1486 KnownZero |= ~InMask & NewMask;
1489 case ISD::BIT_CONVERT:
1491 // If this is an FP->Int bitcast and if the sign bit is the only thing that
1492 // is demanded, turn this into a FGETSIGN.
1493 if (NewMask == EVT::getIntegerVTSignBit(Op.getValueType()) &&
1494 MVT::isFloatingPoint(Op.getOperand(0).getValueType()) &&
1495 !MVT::isVector(Op.getOperand(0).getValueType())) {
1496 // Only do this xform if FGETSIGN is valid or if before legalize.
1497 if (!TLO.AfterLegalize ||
1498 isOperationLegal(ISD::FGETSIGN, Op.getValueType())) {
1499 // Make a FGETSIGN + SHL to move the sign bit into the appropriate
1500 // place. We expect the SHL to be eliminated by other optimizations.
1501 SDValue Sign = TLO.DAG.getNode(ISD::FGETSIGN, Op.getValueType(),
1503 unsigned ShVal = Op.getValueType().getSizeInBits()-1;
1504 SDValue ShAmt = TLO.DAG.getConstant(ShVal, getShiftAmountTy());
1505 return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::SHL, Op.getValueType(),
1514 // Add, Sub, and Mul don't demand any bits in positions beyond that
1515 // of the highest bit demanded of them.
1516 APInt LoMask = APInt::getLowBitsSet(BitWidth,
1517 BitWidth - NewMask.countLeadingZeros());
1518 if (SimplifyDemandedBits(Op.getOperand(0), LoMask, KnownZero2,
1519 KnownOne2, TLO, Depth+1))
1521 if (SimplifyDemandedBits(Op.getOperand(1), LoMask, KnownZero2,
1522 KnownOne2, TLO, Depth+1))
1524 // See if the operation should be performed at a smaller bit width.
1525 if (TLO.ShrinkOps && TLO.ShrinkDemandedOp(Op, BitWidth, NewMask, dl))
1530 // Just use ComputeMaskedBits to compute output bits.
1531 TLO.DAG.ComputeMaskedBits(Op, NewMask, KnownZero, KnownOne, Depth);
1535 // If we know the value of all of the demanded bits, return this as a
1537 if ((NewMask & (KnownZero|KnownOne)) == NewMask)
1538 return TLO.CombineTo(Op, TLO.DAG.getConstant(KnownOne, Op.getValueType()));
1543 /// computeMaskedBitsForTargetNode - Determine which of the bits specified
1544 /// in Mask are known to be either zero or one and return them in the
1545 /// KnownZero/KnownOne bitsets.
1546 void TargetLowering::computeMaskedBitsForTargetNode(const SDValue Op,
1550 const SelectionDAG &DAG,
1551 unsigned Depth) const {
1552 assert((Op.getOpcode() >= ISD::BUILTIN_OP_END ||
1553 Op.getOpcode() == ISD::INTRINSIC_WO_CHAIN ||
1554 Op.getOpcode() == ISD::INTRINSIC_W_CHAIN ||
1555 Op.getOpcode() == ISD::INTRINSIC_VOID) &&
1556 "Should use MaskedValueIsZero if you don't know whether Op"
1557 " is a target node!");
1558 KnownZero = KnownOne = APInt(Mask.getBitWidth(), 0);
1561 /// ComputeNumSignBitsForTargetNode - This method can be implemented by
1562 /// targets that want to expose additional information about sign bits to the
1564 unsigned TargetLowering::ComputeNumSignBitsForTargetNode(SDValue Op,
1565 unsigned Depth) const {
1566 assert((Op.getOpcode() >= ISD::BUILTIN_OP_END ||
1567 Op.getOpcode() == ISD::INTRINSIC_WO_CHAIN ||
1568 Op.getOpcode() == ISD::INTRINSIC_W_CHAIN ||
1569 Op.getOpcode() == ISD::INTRINSIC_VOID) &&
1570 "Should use ComputeNumSignBits if you don't know whether Op"
1571 " is a target node!");
1575 /// ValueHasExactlyOneBitSet - Test if the given value is known to have exactly
1576 /// one bit set. This differs from ComputeMaskedBits in that it doesn't need to
1577 /// determine which bit is set.
1579 static bool ValueHasExactlyOneBitSet(SDValue Val, const SelectionDAG &DAG) {
1580 // A left-shift of a constant one will have exactly one bit set, because
1581 // shifting the bit off the end is undefined.
1582 if (Val.getOpcode() == ISD::SHL)
1583 if (ConstantSDNode *C =
1584 dyn_cast<ConstantSDNode>(Val.getNode()->getOperand(0)))
1585 if (C->getAPIntValue() == 1)
1588 // Similarly, a right-shift of a constant sign-bit will have exactly
1590 if (Val.getOpcode() == ISD::SRL)
1591 if (ConstantSDNode *C =
1592 dyn_cast<ConstantSDNode>(Val.getNode()->getOperand(0)))
1593 if (C->getAPIntValue().isSignBit())
1596 // More could be done here, though the above checks are enough
1597 // to handle some common cases.
1599 // Fall back to ComputeMaskedBits to catch other known cases.
1600 EVT OpVT = Val.getValueType();
1601 unsigned BitWidth = OpVT.getScalarType().getSizeInBits();
1602 APInt Mask = APInt::getAllOnesValue(BitWidth);
1603 APInt KnownZero, KnownOne;
1604 DAG.ComputeMaskedBits(Val, Mask, KnownZero, KnownOne);
1605 return (KnownZero.countPopulation() == BitWidth - 1) &&
1606 (KnownOne.countPopulation() == 1);
1609 /// SimplifySetCC - Try to simplify a setcc built with the specified operands
1610 /// and cc. If it is unable to simplify it, return a null SDValue.
1612 TargetLowering::SimplifySetCC(EVT VT, SDValue N0, SDValue N1,
1613 ISD::CondCode Cond, bool foldBooleans,
1614 DAGCombinerInfo &DCI, DebugLoc dl) const {
1615 SelectionDAG &DAG = DCI.DAG;
1616 LLVMContext &Context = *DAG.getContext();
1618 // These setcc operations always fold.
1622 case ISD::SETFALSE2: return DAG.getConstant(0, VT);
1624 case ISD::SETTRUE2: return DAG.getConstant(1, VT);
1627 if (isa<ConstantSDNode>(N0.getNode())) {
1628 // Ensure that the constant occurs on the RHS, and fold constant
1630 return DAG.getSetCC(dl, VT, N1, N0, ISD::getSetCCSwappedOperands(Cond));
1633 if (ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.getNode())) {
1634 const APInt &C1 = N1C->getAPIntValue();
1636 // If the LHS is '(srl (ctlz x), 5)', the RHS is 0/1, and this is an
1637 // equality comparison, then we're just comparing whether X itself is
1639 if (N0.getOpcode() == ISD::SRL && (C1 == 0 || C1 == 1) &&
1640 N0.getOperand(0).getOpcode() == ISD::CTLZ &&
1641 N0.getOperand(1).getOpcode() == ISD::Constant) {
1643 = cast<ConstantSDNode>(N0.getOperand(1))->getAPIntValue();
1644 if ((Cond == ISD::SETEQ || Cond == ISD::SETNE) &&
1645 ShAmt == Log2_32(N0.getValueType().getSizeInBits())) {
1646 if ((C1 == 0) == (Cond == ISD::SETEQ)) {
1647 // (srl (ctlz x), 5) == 0 -> X != 0
1648 // (srl (ctlz x), 5) != 1 -> X != 0
1651 // (srl (ctlz x), 5) != 0 -> X == 0
1652 // (srl (ctlz x), 5) == 1 -> X == 0
1655 SDValue Zero = DAG.getConstant(0, N0.getValueType());
1656 return DAG.getSetCC(dl, VT, N0.getOperand(0).getOperand(0),
1661 // If the LHS is '(and load, const)', the RHS is 0,
1662 // the test is for equality or unsigned, and all 1 bits of the const are
1663 // in the same partial word, see if we can shorten the load.
1664 if (DCI.isBeforeLegalize() &&
1665 N0.getOpcode() == ISD::AND && C1 == 0 &&
1666 N0.getNode()->hasOneUse() &&
1667 isa<LoadSDNode>(N0.getOperand(0)) &&
1668 N0.getOperand(0).getNode()->hasOneUse() &&
1669 isa<ConstantSDNode>(N0.getOperand(1))) {
1670 LoadSDNode *Lod = cast<LoadSDNode>(N0.getOperand(0));
1672 unsigned bestWidth = 0, bestOffset = 0;
1673 if (!Lod->isVolatile() && Lod->isUnindexed()) {
1674 unsigned origWidth = N0.getValueType().getSizeInBits();
1675 unsigned maskWidth = origWidth;
1676 // We can narrow (e.g.) 16-bit extending loads on 32-bit target to
1677 // 8 bits, but have to be careful...
1678 if (Lod->getExtensionType() != ISD::NON_EXTLOAD)
1679 origWidth = Lod->getMemoryVT().getSizeInBits();
1681 cast<ConstantSDNode>(N0.getOperand(1))->getAPIntValue();
1682 for (unsigned width = origWidth / 2; width>=8; width /= 2) {
1683 APInt newMask = APInt::getLowBitsSet(maskWidth, width);
1684 for (unsigned offset=0; offset<origWidth/width; offset++) {
1685 if ((newMask & Mask) == Mask) {
1686 if (!TD->isLittleEndian())
1687 bestOffset = (origWidth/width - offset - 1) * (width/8);
1689 bestOffset = (uint64_t)offset * (width/8);
1690 bestMask = Mask.lshr(offset * (width/8) * 8);
1694 newMask = newMask << width;
1699 EVT newVT = EVT::getIntegerVT(Context, bestWidth);
1700 if (newVT.isRound()) {
1701 EVT PtrType = Lod->getOperand(1).getValueType();
1702 SDValue Ptr = Lod->getBasePtr();
1703 if (bestOffset != 0)
1704 Ptr = DAG.getNode(ISD::ADD, dl, PtrType, Lod->getBasePtr(),
1705 DAG.getConstant(bestOffset, PtrType));
1706 unsigned NewAlign = MinAlign(Lod->getAlignment(), bestOffset);
1707 SDValue NewLoad = DAG.getLoad(newVT, dl, Lod->getChain(), Ptr,
1709 Lod->getSrcValueOffset() + bestOffset,
1710 false, false, NewAlign);
1711 return DAG.getSetCC(dl, VT,
1712 DAG.getNode(ISD::AND, dl, newVT, NewLoad,
1713 DAG.getConstant(bestMask.trunc(bestWidth),
1715 DAG.getConstant(0LL, newVT), Cond);
1720 // If the LHS is a ZERO_EXTEND, perform the comparison on the input.
1721 if (N0.getOpcode() == ISD::ZERO_EXTEND) {
1722 unsigned InSize = N0.getOperand(0).getValueType().getSizeInBits();
1724 // If the comparison constant has bits in the upper part, the
1725 // zero-extended value could never match.
1726 if (C1.intersects(APInt::getHighBitsSet(C1.getBitWidth(),
1727 C1.getBitWidth() - InSize))) {
1731 case ISD::SETEQ: return DAG.getConstant(0, VT);
1734 case ISD::SETNE: return DAG.getConstant(1, VT);
1737 // True if the sign bit of C1 is set.
1738 return DAG.getConstant(C1.isNegative(), VT);
1741 // True if the sign bit of C1 isn't set.
1742 return DAG.getConstant(C1.isNonNegative(), VT);
1748 // Otherwise, we can perform the comparison with the low bits.
1756 EVT newVT = N0.getOperand(0).getValueType();
1757 if (DCI.isBeforeLegalizeOps() ||
1758 (isOperationLegal(ISD::SETCC, newVT) &&
1759 getCondCodeAction(Cond, newVT)==Legal))
1760 return DAG.getSetCC(dl, VT, N0.getOperand(0),
1761 DAG.getConstant(APInt(C1).trunc(InSize), newVT),
1766 break; // todo, be more careful with signed comparisons
1768 } else if (N0.getOpcode() == ISD::SIGN_EXTEND_INREG &&
1769 (Cond == ISD::SETEQ || Cond == ISD::SETNE)) {
1770 EVT ExtSrcTy = cast<VTSDNode>(N0.getOperand(1))->getVT();
1771 unsigned ExtSrcTyBits = ExtSrcTy.getSizeInBits();
1772 EVT ExtDstTy = N0.getValueType();
1773 unsigned ExtDstTyBits = ExtDstTy.getSizeInBits();
1775 // If the extended part has any inconsistent bits, it cannot ever
1776 // compare equal. In other words, they have to be all ones or all
1779 APInt::getHighBitsSet(ExtDstTyBits, ExtDstTyBits - ExtSrcTyBits);
1780 if ((C1 & ExtBits) != 0 && (C1 & ExtBits) != ExtBits)
1781 return DAG.getConstant(Cond == ISD::SETNE, VT);
1784 EVT Op0Ty = N0.getOperand(0).getValueType();
1785 if (Op0Ty == ExtSrcTy) {
1786 ZextOp = N0.getOperand(0);
1788 APInt Imm = APInt::getLowBitsSet(ExtDstTyBits, ExtSrcTyBits);
1789 ZextOp = DAG.getNode(ISD::AND, dl, Op0Ty, N0.getOperand(0),
1790 DAG.getConstant(Imm, Op0Ty));
1792 if (!DCI.isCalledByLegalizer())
1793 DCI.AddToWorklist(ZextOp.getNode());
1794 // Otherwise, make this a use of a zext.
1795 return DAG.getSetCC(dl, VT, ZextOp,
1796 DAG.getConstant(C1 & APInt::getLowBitsSet(
1801 } else if ((N1C->isNullValue() || N1C->getAPIntValue() == 1) &&
1802 (Cond == ISD::SETEQ || Cond == ISD::SETNE)) {
1803 // SETCC (SETCC), [0|1], [EQ|NE] -> SETCC
1804 if (N0.getOpcode() == ISD::SETCC &&
1805 isTypeLegal(VT) && VT.bitsLE(N0.getValueType())) {
1806 bool TrueWhenTrue = (Cond == ISD::SETEQ) ^ (N1C->getAPIntValue() != 1);
1808 return DAG.getNode(ISD::TRUNCATE, dl, VT, N0);
1809 // Invert the condition.
1810 ISD::CondCode CC = cast<CondCodeSDNode>(N0.getOperand(2))->get();
1811 CC = ISD::getSetCCInverse(CC,
1812 N0.getOperand(0).getValueType().isInteger());
1813 return DAG.getSetCC(dl, VT, N0.getOperand(0), N0.getOperand(1), CC);
1816 if ((N0.getOpcode() == ISD::XOR ||
1817 (N0.getOpcode() == ISD::AND &&
1818 N0.getOperand(0).getOpcode() == ISD::XOR &&
1819 N0.getOperand(1) == N0.getOperand(0).getOperand(1))) &&
1820 isa<ConstantSDNode>(N0.getOperand(1)) &&
1821 cast<ConstantSDNode>(N0.getOperand(1))->getAPIntValue() == 1) {
1822 // If this is (X^1) == 0/1, swap the RHS and eliminate the xor. We
1823 // can only do this if the top bits are known zero.
1824 unsigned BitWidth = N0.getValueSizeInBits();
1825 if (DAG.MaskedValueIsZero(N0,
1826 APInt::getHighBitsSet(BitWidth,
1828 // Okay, get the un-inverted input value.
1830 if (N0.getOpcode() == ISD::XOR)
1831 Val = N0.getOperand(0);
1833 assert(N0.getOpcode() == ISD::AND &&
1834 N0.getOperand(0).getOpcode() == ISD::XOR);
1835 // ((X^1)&1)^1 -> X & 1
1836 Val = DAG.getNode(ISD::AND, dl, N0.getValueType(),
1837 N0.getOperand(0).getOperand(0),
1841 return DAG.getSetCC(dl, VT, Val, N1,
1842 Cond == ISD::SETEQ ? ISD::SETNE : ISD::SETEQ);
1844 } else if (N1C->getAPIntValue() == 1 &&
1846 getBooleanContents() == ZeroOrOneBooleanContent)) {
1848 if (Op0.getOpcode() == ISD::TRUNCATE)
1849 Op0 = Op0.getOperand(0);
1851 if ((Op0.getOpcode() == ISD::XOR) &&
1852 Op0.getOperand(0).getOpcode() == ISD::SETCC &&
1853 Op0.getOperand(1).getOpcode() == ISD::SETCC) {
1854 // (xor (setcc), (setcc)) == / != 1 -> (setcc) != / == (setcc)
1855 Cond = (Cond == ISD::SETEQ) ? ISD::SETNE : ISD::SETEQ;
1856 return DAG.getSetCC(dl, VT, Op0.getOperand(0), Op0.getOperand(1),
1858 } else if (Op0.getOpcode() == ISD::AND &&
1859 isa<ConstantSDNode>(Op0.getOperand(1)) &&
1860 cast<ConstantSDNode>(Op0.getOperand(1))->getAPIntValue() == 1) {
1861 // If this is (X&1) == / != 1, normalize it to (X&1) != / == 0.
1862 if (Op0.getValueType() != VT)
1863 Op0 = DAG.getNode(ISD::AND, dl, VT,
1864 DAG.getNode(ISD::TRUNCATE, dl, VT, Op0.getOperand(0)),
1865 DAG.getConstant(1, VT));
1866 return DAG.getSetCC(dl, VT, Op0,
1867 DAG.getConstant(0, Op0.getValueType()),
1868 Cond == ISD::SETEQ ? ISD::SETNE : ISD::SETEQ);
1873 APInt MinVal, MaxVal;
1874 unsigned OperandBitSize = N1C->getValueType(0).getSizeInBits();
1875 if (ISD::isSignedIntSetCC(Cond)) {
1876 MinVal = APInt::getSignedMinValue(OperandBitSize);
1877 MaxVal = APInt::getSignedMaxValue(OperandBitSize);
1879 MinVal = APInt::getMinValue(OperandBitSize);
1880 MaxVal = APInt::getMaxValue(OperandBitSize);
1883 // Canonicalize GE/LE comparisons to use GT/LT comparisons.
1884 if (Cond == ISD::SETGE || Cond == ISD::SETUGE) {
1885 if (C1 == MinVal) return DAG.getConstant(1, VT); // X >= MIN --> true
1886 // X >= C0 --> X > (C0-1)
1887 return DAG.getSetCC(dl, VT, N0,
1888 DAG.getConstant(C1-1, N1.getValueType()),
1889 (Cond == ISD::SETGE) ? ISD::SETGT : ISD::SETUGT);
1892 if (Cond == ISD::SETLE || Cond == ISD::SETULE) {
1893 if (C1 == MaxVal) return DAG.getConstant(1, VT); // X <= MAX --> true
1894 // X <= C0 --> X < (C0+1)
1895 return DAG.getSetCC(dl, VT, N0,
1896 DAG.getConstant(C1+1, N1.getValueType()),
1897 (Cond == ISD::SETLE) ? ISD::SETLT : ISD::SETULT);
1900 if ((Cond == ISD::SETLT || Cond == ISD::SETULT) && C1 == MinVal)
1901 return DAG.getConstant(0, VT); // X < MIN --> false
1902 if ((Cond == ISD::SETGE || Cond == ISD::SETUGE) && C1 == MinVal)
1903 return DAG.getConstant(1, VT); // X >= MIN --> true
1904 if ((Cond == ISD::SETGT || Cond == ISD::SETUGT) && C1 == MaxVal)
1905 return DAG.getConstant(0, VT); // X > MAX --> false
1906 if ((Cond == ISD::SETLE || Cond == ISD::SETULE) && C1 == MaxVal)
1907 return DAG.getConstant(1, VT); // X <= MAX --> true
1909 // Canonicalize setgt X, Min --> setne X, Min
1910 if ((Cond == ISD::SETGT || Cond == ISD::SETUGT) && C1 == MinVal)
1911 return DAG.getSetCC(dl, VT, N0, N1, ISD::SETNE);
1912 // Canonicalize setlt X, Max --> setne X, Max
1913 if ((Cond == ISD::SETLT || Cond == ISD::SETULT) && C1 == MaxVal)
1914 return DAG.getSetCC(dl, VT, N0, N1, ISD::SETNE);
1916 // If we have setult X, 1, turn it into seteq X, 0
1917 if ((Cond == ISD::SETLT || Cond == ISD::SETULT) && C1 == MinVal+1)
1918 return DAG.getSetCC(dl, VT, N0,
1919 DAG.getConstant(MinVal, N0.getValueType()),
1921 // If we have setugt X, Max-1, turn it into seteq X, Max
1922 else if ((Cond == ISD::SETGT || Cond == ISD::SETUGT) && C1 == MaxVal-1)
1923 return DAG.getSetCC(dl, VT, N0,
1924 DAG.getConstant(MaxVal, N0.getValueType()),
1927 // If we have "setcc X, C0", check to see if we can shrink the immediate
1930 // SETUGT X, SINTMAX -> SETLT X, 0
1931 if (Cond == ISD::SETUGT &&
1932 C1 == APInt::getSignedMaxValue(OperandBitSize))
1933 return DAG.getSetCC(dl, VT, N0,
1934 DAG.getConstant(0, N1.getValueType()),
1937 // SETULT X, SINTMIN -> SETGT X, -1
1938 if (Cond == ISD::SETULT &&
1939 C1 == APInt::getSignedMinValue(OperandBitSize)) {
1940 SDValue ConstMinusOne =
1941 DAG.getConstant(APInt::getAllOnesValue(OperandBitSize),
1943 return DAG.getSetCC(dl, VT, N0, ConstMinusOne, ISD::SETGT);
1946 // Fold bit comparisons when we can.
1947 if ((Cond == ISD::SETEQ || Cond == ISD::SETNE) &&
1948 (VT == N0.getValueType() ||
1949 (isTypeLegal(VT) && VT.bitsLE(N0.getValueType()))) &&
1950 N0.getOpcode() == ISD::AND)
1951 if (ConstantSDNode *AndRHS =
1952 dyn_cast<ConstantSDNode>(N0.getOperand(1))) {
1953 EVT ShiftTy = DCI.isBeforeLegalize() ?
1954 getPointerTy() : getShiftAmountTy();
1955 if (Cond == ISD::SETNE && C1 == 0) {// (X & 8) != 0 --> (X & 8) >> 3
1956 // Perform the xform if the AND RHS is a single bit.
1957 if (AndRHS->getAPIntValue().isPowerOf2()) {
1958 return DAG.getNode(ISD::TRUNCATE, dl, VT,
1959 DAG.getNode(ISD::SRL, dl, N0.getValueType(), N0,
1960 DAG.getConstant(AndRHS->getAPIntValue().logBase2(), ShiftTy)));
1962 } else if (Cond == ISD::SETEQ && C1 == AndRHS->getAPIntValue()) {
1963 // (X & 8) == 8 --> (X & 8) >> 3
1964 // Perform the xform if C1 is a single bit.
1965 if (C1.isPowerOf2()) {
1966 return DAG.getNode(ISD::TRUNCATE, dl, VT,
1967 DAG.getNode(ISD::SRL, dl, N0.getValueType(), N0,
1968 DAG.getConstant(C1.logBase2(), ShiftTy)));
1974 if (isa<ConstantFPSDNode>(N0.getNode())) {
1975 // Constant fold or commute setcc.
1976 SDValue O = DAG.FoldSetCC(VT, N0, N1, Cond, dl);
1977 if (O.getNode()) return O;
1978 } else if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(N1.getNode())) {
1979 // If the RHS of an FP comparison is a constant, simplify it away in
1981 if (CFP->getValueAPF().isNaN()) {
1982 // If an operand is known to be a nan, we can fold it.
1983 switch (ISD::getUnorderedFlavor(Cond)) {
1984 default: llvm_unreachable("Unknown flavor!");
1985 case 0: // Known false.
1986 return DAG.getConstant(0, VT);
1987 case 1: // Known true.
1988 return DAG.getConstant(1, VT);
1989 case 2: // Undefined.
1990 return DAG.getUNDEF(VT);
1994 // Otherwise, we know the RHS is not a NaN. Simplify the node to drop the
1995 // constant if knowing that the operand is non-nan is enough. We prefer to
1996 // have SETO(x,x) instead of SETO(x, 0.0) because this avoids having to
1998 if (Cond == ISD::SETO || Cond == ISD::SETUO)
1999 return DAG.getSetCC(dl, VT, N0, N0, Cond);
2001 // If the condition is not legal, see if we can find an equivalent one
2003 if (!isCondCodeLegal(Cond, N0.getValueType())) {
2004 // If the comparison was an awkward floating-point == or != and one of
2005 // the comparison operands is infinity or negative infinity, convert the
2006 // condition to a less-awkward <= or >=.
2007 if (CFP->getValueAPF().isInfinity()) {
2008 if (CFP->getValueAPF().isNegative()) {
2009 if (Cond == ISD::SETOEQ &&
2010 isCondCodeLegal(ISD::SETOLE, N0.getValueType()))
2011 return DAG.getSetCC(dl, VT, N0, N1, ISD::SETOLE);
2012 if (Cond == ISD::SETUEQ &&
2013 isCondCodeLegal(ISD::SETOLE, N0.getValueType()))
2014 return DAG.getSetCC(dl, VT, N0, N1, ISD::SETULE);
2015 if (Cond == ISD::SETUNE &&
2016 isCondCodeLegal(ISD::SETUGT, N0.getValueType()))
2017 return DAG.getSetCC(dl, VT, N0, N1, ISD::SETUGT);
2018 if (Cond == ISD::SETONE &&
2019 isCondCodeLegal(ISD::SETUGT, N0.getValueType()))
2020 return DAG.getSetCC(dl, VT, N0, N1, ISD::SETOGT);
2022 if (Cond == ISD::SETOEQ &&
2023 isCondCodeLegal(ISD::SETOGE, N0.getValueType()))
2024 return DAG.getSetCC(dl, VT, N0, N1, ISD::SETOGE);
2025 if (Cond == ISD::SETUEQ &&
2026 isCondCodeLegal(ISD::SETOGE, N0.getValueType()))
2027 return DAG.getSetCC(dl, VT, N0, N1, ISD::SETUGE);
2028 if (Cond == ISD::SETUNE &&
2029 isCondCodeLegal(ISD::SETULT, N0.getValueType()))
2030 return DAG.getSetCC(dl, VT, N0, N1, ISD::SETULT);
2031 if (Cond == ISD::SETONE &&
2032 isCondCodeLegal(ISD::SETULT, N0.getValueType()))
2033 return DAG.getSetCC(dl, VT, N0, N1, ISD::SETOLT);
2040 // We can always fold X == X for integer setcc's.
2041 if (N0.getValueType().isInteger())
2042 return DAG.getConstant(ISD::isTrueWhenEqual(Cond), VT);
2043 unsigned UOF = ISD::getUnorderedFlavor(Cond);
2044 if (UOF == 2) // FP operators that are undefined on NaNs.
2045 return DAG.getConstant(ISD::isTrueWhenEqual(Cond), VT);
2046 if (UOF == unsigned(ISD::isTrueWhenEqual(Cond)))
2047 return DAG.getConstant(UOF, VT);
2048 // Otherwise, we can't fold it. However, we can simplify it to SETUO/SETO
2049 // if it is not already.
2050 ISD::CondCode NewCond = UOF == 0 ? ISD::SETO : ISD::SETUO;
2051 if (NewCond != Cond)
2052 return DAG.getSetCC(dl, VT, N0, N1, NewCond);
2055 if ((Cond == ISD::SETEQ || Cond == ISD::SETNE) &&
2056 N0.getValueType().isInteger()) {
2057 if (N0.getOpcode() == ISD::ADD || N0.getOpcode() == ISD::SUB ||
2058 N0.getOpcode() == ISD::XOR) {
2059 // Simplify (X+Y) == (X+Z) --> Y == Z
2060 if (N0.getOpcode() == N1.getOpcode()) {
2061 if (N0.getOperand(0) == N1.getOperand(0))
2062 return DAG.getSetCC(dl, VT, N0.getOperand(1), N1.getOperand(1), Cond);
2063 if (N0.getOperand(1) == N1.getOperand(1))
2064 return DAG.getSetCC(dl, VT, N0.getOperand(0), N1.getOperand(0), Cond);
2065 if (DAG.isCommutativeBinOp(N0.getOpcode())) {
2066 // If X op Y == Y op X, try other combinations.
2067 if (N0.getOperand(0) == N1.getOperand(1))
2068 return DAG.getSetCC(dl, VT, N0.getOperand(1), N1.getOperand(0),
2070 if (N0.getOperand(1) == N1.getOperand(0))
2071 return DAG.getSetCC(dl, VT, N0.getOperand(0), N1.getOperand(1),
2076 if (ConstantSDNode *RHSC = dyn_cast<ConstantSDNode>(N1)) {
2077 if (ConstantSDNode *LHSR = dyn_cast<ConstantSDNode>(N0.getOperand(1))) {
2078 // Turn (X+C1) == C2 --> X == C2-C1
2079 if (N0.getOpcode() == ISD::ADD && N0.getNode()->hasOneUse()) {
2080 return DAG.getSetCC(dl, VT, N0.getOperand(0),
2081 DAG.getConstant(RHSC->getAPIntValue()-
2082 LHSR->getAPIntValue(),
2083 N0.getValueType()), Cond);
2086 // Turn (X^C1) == C2 into X == C1^C2 iff X&~C1 = 0.
2087 if (N0.getOpcode() == ISD::XOR)
2088 // If we know that all of the inverted bits are zero, don't bother
2089 // performing the inversion.
2090 if (DAG.MaskedValueIsZero(N0.getOperand(0), ~LHSR->getAPIntValue()))
2092 DAG.getSetCC(dl, VT, N0.getOperand(0),
2093 DAG.getConstant(LHSR->getAPIntValue() ^
2094 RHSC->getAPIntValue(),
2099 // Turn (C1-X) == C2 --> X == C1-C2
2100 if (ConstantSDNode *SUBC = dyn_cast<ConstantSDNode>(N0.getOperand(0))) {
2101 if (N0.getOpcode() == ISD::SUB && N0.getNode()->hasOneUse()) {
2103 DAG.getSetCC(dl, VT, N0.getOperand(1),
2104 DAG.getConstant(SUBC->getAPIntValue() -
2105 RHSC->getAPIntValue(),
2112 // Simplify (X+Z) == X --> Z == 0
2113 if (N0.getOperand(0) == N1)
2114 return DAG.getSetCC(dl, VT, N0.getOperand(1),
2115 DAG.getConstant(0, N0.getValueType()), Cond);
2116 if (N0.getOperand(1) == N1) {
2117 if (DAG.isCommutativeBinOp(N0.getOpcode()))
2118 return DAG.getSetCC(dl, VT, N0.getOperand(0),
2119 DAG.getConstant(0, N0.getValueType()), Cond);
2120 else if (N0.getNode()->hasOneUse()) {
2121 assert(N0.getOpcode() == ISD::SUB && "Unexpected operation!");
2122 // (Z-X) == X --> Z == X<<1
2123 SDValue SH = DAG.getNode(ISD::SHL, dl, N1.getValueType(),
2125 DAG.getConstant(1, getShiftAmountTy()));
2126 if (!DCI.isCalledByLegalizer())
2127 DCI.AddToWorklist(SH.getNode());
2128 return DAG.getSetCC(dl, VT, N0.getOperand(0), SH, Cond);
2133 if (N1.getOpcode() == ISD::ADD || N1.getOpcode() == ISD::SUB ||
2134 N1.getOpcode() == ISD::XOR) {
2135 // Simplify X == (X+Z) --> Z == 0
2136 if (N1.getOperand(0) == N0) {
2137 return DAG.getSetCC(dl, VT, N1.getOperand(1),
2138 DAG.getConstant(0, N1.getValueType()), Cond);
2139 } else if (N1.getOperand(1) == N0) {
2140 if (DAG.isCommutativeBinOp(N1.getOpcode())) {
2141 return DAG.getSetCC(dl, VT, N1.getOperand(0),
2142 DAG.getConstant(0, N1.getValueType()), Cond);
2143 } else if (N1.getNode()->hasOneUse()) {
2144 assert(N1.getOpcode() == ISD::SUB && "Unexpected operation!");
2145 // X == (Z-X) --> X<<1 == Z
2146 SDValue SH = DAG.getNode(ISD::SHL, dl, N1.getValueType(), N0,
2147 DAG.getConstant(1, getShiftAmountTy()));
2148 if (!DCI.isCalledByLegalizer())
2149 DCI.AddToWorklist(SH.getNode());
2150 return DAG.getSetCC(dl, VT, SH, N1.getOperand(0), Cond);
2155 // Simplify x&y == y to x&y != 0 if y has exactly one bit set.
2156 // Note that where y is variable and is known to have at most
2157 // one bit set (for example, if it is z&1) we cannot do this;
2158 // the expressions are not equivalent when y==0.
2159 if (N0.getOpcode() == ISD::AND)
2160 if (N0.getOperand(0) == N1 || N0.getOperand(1) == N1) {
2161 if (ValueHasExactlyOneBitSet(N1, DAG)) {
2162 Cond = ISD::getSetCCInverse(Cond, /*isInteger=*/true);
2163 SDValue Zero = DAG.getConstant(0, N1.getValueType());
2164 return DAG.getSetCC(dl, VT, N0, Zero, Cond);
2167 if (N1.getOpcode() == ISD::AND)
2168 if (N1.getOperand(0) == N0 || N1.getOperand(1) == N0) {
2169 if (ValueHasExactlyOneBitSet(N0, DAG)) {
2170 Cond = ISD::getSetCCInverse(Cond, /*isInteger=*/true);
2171 SDValue Zero = DAG.getConstant(0, N0.getValueType());
2172 return DAG.getSetCC(dl, VT, N1, Zero, Cond);
2177 // Fold away ALL boolean setcc's.
2179 if (N0.getValueType() == MVT::i1 && foldBooleans) {
2181 default: llvm_unreachable("Unknown integer setcc!");
2182 case ISD::SETEQ: // X == Y -> ~(X^Y)
2183 Temp = DAG.getNode(ISD::XOR, dl, MVT::i1, N0, N1);
2184 N0 = DAG.getNOT(dl, Temp, MVT::i1);
2185 if (!DCI.isCalledByLegalizer())
2186 DCI.AddToWorklist(Temp.getNode());
2188 case ISD::SETNE: // X != Y --> (X^Y)
2189 N0 = DAG.getNode(ISD::XOR, dl, MVT::i1, N0, N1);
2191 case ISD::SETGT: // X >s Y --> X == 0 & Y == 1 --> ~X & Y
2192 case ISD::SETULT: // X <u Y --> X == 0 & Y == 1 --> ~X & Y
2193 Temp = DAG.getNOT(dl, N0, MVT::i1);
2194 N0 = DAG.getNode(ISD::AND, dl, MVT::i1, N1, Temp);
2195 if (!DCI.isCalledByLegalizer())
2196 DCI.AddToWorklist(Temp.getNode());
2198 case ISD::SETLT: // X <s Y --> X == 1 & Y == 0 --> ~Y & X
2199 case ISD::SETUGT: // X >u Y --> X == 1 & Y == 0 --> ~Y & X
2200 Temp = DAG.getNOT(dl, N1, MVT::i1);
2201 N0 = DAG.getNode(ISD::AND, dl, MVT::i1, N0, Temp);
2202 if (!DCI.isCalledByLegalizer())
2203 DCI.AddToWorklist(Temp.getNode());
2205 case ISD::SETULE: // X <=u Y --> X == 0 | Y == 1 --> ~X | Y
2206 case ISD::SETGE: // X >=s Y --> X == 0 | Y == 1 --> ~X | Y
2207 Temp = DAG.getNOT(dl, N0, MVT::i1);
2208 N0 = DAG.getNode(ISD::OR, dl, MVT::i1, N1, Temp);
2209 if (!DCI.isCalledByLegalizer())
2210 DCI.AddToWorklist(Temp.getNode());
2212 case ISD::SETUGE: // X >=u Y --> X == 1 | Y == 0 --> ~Y | X
2213 case ISD::SETLE: // X <=s Y --> X == 1 | Y == 0 --> ~Y | X
2214 Temp = DAG.getNOT(dl, N1, MVT::i1);
2215 N0 = DAG.getNode(ISD::OR, dl, MVT::i1, N0, Temp);
2218 if (VT != MVT::i1) {
2219 if (!DCI.isCalledByLegalizer())
2220 DCI.AddToWorklist(N0.getNode());
2221 // FIXME: If running after legalize, we probably can't do this.
2222 N0 = DAG.getNode(ISD::ZERO_EXTEND, dl, VT, N0);
2227 // Could not fold it.
2231 /// isGAPlusOffset - Returns true (and the GlobalValue and the offset) if the
2232 /// node is a GlobalAddress + offset.
2233 bool TargetLowering::isGAPlusOffset(SDNode *N, GlobalValue* &GA,
2234 int64_t &Offset) const {
2235 if (isa<GlobalAddressSDNode>(N)) {
2236 GlobalAddressSDNode *GASD = cast<GlobalAddressSDNode>(N);
2237 GA = GASD->getGlobal();
2238 Offset += GASD->getOffset();
2242 if (N->getOpcode() == ISD::ADD) {
2243 SDValue N1 = N->getOperand(0);
2244 SDValue N2 = N->getOperand(1);
2245 if (isGAPlusOffset(N1.getNode(), GA, Offset)) {
2246 ConstantSDNode *V = dyn_cast<ConstantSDNode>(N2);
2248 Offset += V->getSExtValue();
2251 } else if (isGAPlusOffset(N2.getNode(), GA, Offset)) {
2252 ConstantSDNode *V = dyn_cast<ConstantSDNode>(N1);
2254 Offset += V->getSExtValue();
2263 SDValue TargetLowering::
2264 PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const {
2265 // Default implementation: no optimization.
2269 //===----------------------------------------------------------------------===//
2270 // Inline Assembler Implementation Methods
2271 //===----------------------------------------------------------------------===//
2274 TargetLowering::ConstraintType
2275 TargetLowering::getConstraintType(const std::string &Constraint) const {
2276 // FIXME: lots more standard ones to handle.
2277 if (Constraint.size() == 1) {
2278 switch (Constraint[0]) {
2280 case 'r': return C_RegisterClass;
2282 case 'o': // offsetable
2283 case 'V': // not offsetable
2285 case 'i': // Simple Integer or Relocatable Constant
2286 case 'n': // Simple Integer
2287 case 's': // Relocatable Constant
2288 case 'X': // Allow ANY value.
2289 case 'I': // Target registers.
2301 if (Constraint.size() > 1 && Constraint[0] == '{' &&
2302 Constraint[Constraint.size()-1] == '}')
2307 /// LowerXConstraint - try to replace an X constraint, which matches anything,
2308 /// with another that has more specific requirements based on the type of the
2309 /// corresponding operand.
2310 const char *TargetLowering::LowerXConstraint(EVT ConstraintVT) const{
2311 if (ConstraintVT.isInteger())
2313 if (ConstraintVT.isFloatingPoint())
2314 return "f"; // works for many targets
2318 /// LowerAsmOperandForConstraint - Lower the specified operand into the Ops
2319 /// vector. If it is invalid, don't add anything to Ops.
2320 void TargetLowering::LowerAsmOperandForConstraint(SDValue Op,
2321 char ConstraintLetter,
2323 std::vector<SDValue> &Ops,
2324 SelectionDAG &DAG) const {
2325 switch (ConstraintLetter) {
2327 case 'X': // Allows any operand; labels (basic block) use this.
2328 if (Op.getOpcode() == ISD::BasicBlock) {
2333 case 'i': // Simple Integer or Relocatable Constant
2334 case 'n': // Simple Integer
2335 case 's': { // Relocatable Constant
2336 // These operands are interested in values of the form (GV+C), where C may
2337 // be folded in as an offset of GV, or it may be explicitly added. Also, it
2338 // is possible and fine if either GV or C are missing.
2339 ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op);
2340 GlobalAddressSDNode *GA = dyn_cast<GlobalAddressSDNode>(Op);
2342 // If we have "(add GV, C)", pull out GV/C
2343 if (Op.getOpcode() == ISD::ADD) {
2344 C = dyn_cast<ConstantSDNode>(Op.getOperand(1));
2345 GA = dyn_cast<GlobalAddressSDNode>(Op.getOperand(0));
2346 if (C == 0 || GA == 0) {
2347 C = dyn_cast<ConstantSDNode>(Op.getOperand(0));
2348 GA = dyn_cast<GlobalAddressSDNode>(Op.getOperand(1));
2350 if (C == 0 || GA == 0)
2354 // If we find a valid operand, map to the TargetXXX version so that the
2355 // value itself doesn't get selected.
2356 if (GA) { // Either &GV or &GV+C
2357 if (ConstraintLetter != 'n') {
2358 int64_t Offs = GA->getOffset();
2359 if (C) Offs += C->getZExtValue();
2360 Ops.push_back(DAG.getTargetGlobalAddress(GA->getGlobal(),
2361 Op.getValueType(), Offs));
2365 if (C) { // just C, no GV.
2366 // Simple constants are not allowed for 's'.
2367 if (ConstraintLetter != 's') {
2368 // gcc prints these as sign extended. Sign extend value to 64 bits
2369 // now; without this it would get ZExt'd later in
2370 // ScheduleDAGSDNodes::EmitNode, which is very generic.
2371 Ops.push_back(DAG.getTargetConstant(C->getAPIntValue().getSExtValue(),
2381 std::vector<unsigned> TargetLowering::
2382 getRegClassForInlineAsmConstraint(const std::string &Constraint,
2384 return std::vector<unsigned>();
2388 std::pair<unsigned, const TargetRegisterClass*> TargetLowering::
2389 getRegForInlineAsmConstraint(const std::string &Constraint,
2391 if (Constraint[0] != '{')
2392 return std::pair<unsigned, const TargetRegisterClass*>(0, 0);
2393 assert(*(Constraint.end()-1) == '}' && "Not a brace enclosed constraint?");
2395 // Remove the braces from around the name.
2396 StringRef RegName(Constraint.data()+1, Constraint.size()-2);
2398 // Figure out which register class contains this reg.
2399 const TargetRegisterInfo *RI = TM.getRegisterInfo();
2400 for (TargetRegisterInfo::regclass_iterator RCI = RI->regclass_begin(),
2401 E = RI->regclass_end(); RCI != E; ++RCI) {
2402 const TargetRegisterClass *RC = *RCI;
2404 // If none of the value types for this register class are valid, we
2405 // can't use it. For example, 64-bit reg classes on 32-bit targets.
2406 bool isLegal = false;
2407 for (TargetRegisterClass::vt_iterator I = RC->vt_begin(), E = RC->vt_end();
2409 if (isTypeLegal(*I)) {
2415 if (!isLegal) continue;
2417 for (TargetRegisterClass::iterator I = RC->begin(), E = RC->end();
2419 if (RegName.equals_lower(RI->getName(*I)))
2420 return std::make_pair(*I, RC);
2424 return std::pair<unsigned, const TargetRegisterClass*>(0, 0);
2427 //===----------------------------------------------------------------------===//
2428 // Constraint Selection.
2430 /// isMatchingInputConstraint - Return true of this is an input operand that is
2431 /// a matching constraint like "4".
2432 bool TargetLowering::AsmOperandInfo::isMatchingInputConstraint() const {
2433 assert(!ConstraintCode.empty() && "No known constraint!");
2434 return isdigit(ConstraintCode[0]);
2437 /// getMatchedOperand - If this is an input matching constraint, this method
2438 /// returns the output operand it matches.
2439 unsigned TargetLowering::AsmOperandInfo::getMatchedOperand() const {
2440 assert(!ConstraintCode.empty() && "No known constraint!");
2441 return atoi(ConstraintCode.c_str());
2445 /// getConstraintGenerality - Return an integer indicating how general CT
2447 static unsigned getConstraintGenerality(TargetLowering::ConstraintType CT) {
2449 default: llvm_unreachable("Unknown constraint type!");
2450 case TargetLowering::C_Other:
2451 case TargetLowering::C_Unknown:
2453 case TargetLowering::C_Register:
2455 case TargetLowering::C_RegisterClass:
2457 case TargetLowering::C_Memory:
2462 /// ChooseConstraint - If there are multiple different constraints that we
2463 /// could pick for this operand (e.g. "imr") try to pick the 'best' one.
2464 /// This is somewhat tricky: constraints fall into four classes:
2465 /// Other -> immediates and magic values
2466 /// Register -> one specific register
2467 /// RegisterClass -> a group of regs
2468 /// Memory -> memory
2469 /// Ideally, we would pick the most specific constraint possible: if we have
2470 /// something that fits into a register, we would pick it. The problem here
2471 /// is that if we have something that could either be in a register or in
2472 /// memory that use of the register could cause selection of *other*
2473 /// operands to fail: they might only succeed if we pick memory. Because of
2474 /// this the heuristic we use is:
2476 /// 1) If there is an 'other' constraint, and if the operand is valid for
2477 /// that constraint, use it. This makes us take advantage of 'i'
2478 /// constraints when available.
2479 /// 2) Otherwise, pick the most general constraint present. This prefers
2480 /// 'm' over 'r', for example.
2482 static void ChooseConstraint(TargetLowering::AsmOperandInfo &OpInfo,
2483 bool hasMemory, const TargetLowering &TLI,
2484 SDValue Op, SelectionDAG *DAG) {
2485 assert(OpInfo.Codes.size() > 1 && "Doesn't have multiple constraint options");
2486 unsigned BestIdx = 0;
2487 TargetLowering::ConstraintType BestType = TargetLowering::C_Unknown;
2488 int BestGenerality = -1;
2490 // Loop over the options, keeping track of the most general one.
2491 for (unsigned i = 0, e = OpInfo.Codes.size(); i != e; ++i) {
2492 TargetLowering::ConstraintType CType =
2493 TLI.getConstraintType(OpInfo.Codes[i]);
2495 // If this is an 'other' constraint, see if the operand is valid for it.
2496 // For example, on X86 we might have an 'rI' constraint. If the operand
2497 // is an integer in the range [0..31] we want to use I (saving a load
2498 // of a register), otherwise we must use 'r'.
2499 if (CType == TargetLowering::C_Other && Op.getNode()) {
2500 assert(OpInfo.Codes[i].size() == 1 &&
2501 "Unhandled multi-letter 'other' constraint");
2502 std::vector<SDValue> ResultOps;
2503 TLI.LowerAsmOperandForConstraint(Op, OpInfo.Codes[i][0], hasMemory,
2505 if (!ResultOps.empty()) {
2512 // This constraint letter is more general than the previous one, use it.
2513 int Generality = getConstraintGenerality(CType);
2514 if (Generality > BestGenerality) {
2517 BestGenerality = Generality;
2521 OpInfo.ConstraintCode = OpInfo.Codes[BestIdx];
2522 OpInfo.ConstraintType = BestType;
2525 /// ComputeConstraintToUse - Determines the constraint code and constraint
2526 /// type to use for the specific AsmOperandInfo, setting
2527 /// OpInfo.ConstraintCode and OpInfo.ConstraintType.
2528 void TargetLowering::ComputeConstraintToUse(AsmOperandInfo &OpInfo,
2531 SelectionDAG *DAG) const {
2532 assert(!OpInfo.Codes.empty() && "Must have at least one constraint");
2534 // Single-letter constraints ('r') are very common.
2535 if (OpInfo.Codes.size() == 1) {
2536 OpInfo.ConstraintCode = OpInfo.Codes[0];
2537 OpInfo.ConstraintType = getConstraintType(OpInfo.ConstraintCode);
2539 ChooseConstraint(OpInfo, hasMemory, *this, Op, DAG);
2542 // 'X' matches anything.
2543 if (OpInfo.ConstraintCode == "X" && OpInfo.CallOperandVal) {
2544 // Labels and constants are handled elsewhere ('X' is the only thing
2545 // that matches labels). For Functions, the type here is the type of
2546 // the result, which is not what we want to look at; leave them alone.
2547 Value *v = OpInfo.CallOperandVal;
2548 if (isa<BasicBlock>(v) || isa<ConstantInt>(v) || isa<Function>(v)) {
2549 OpInfo.CallOperandVal = v;
2553 // Otherwise, try to resolve it to something we know about by looking at
2554 // the actual operand type.
2555 if (const char *Repl = LowerXConstraint(OpInfo.ConstraintVT)) {
2556 OpInfo.ConstraintCode = Repl;
2557 OpInfo.ConstraintType = getConstraintType(OpInfo.ConstraintCode);
2562 //===----------------------------------------------------------------------===//
2563 // Loop Strength Reduction hooks
2564 //===----------------------------------------------------------------------===//
2566 /// isLegalAddressingMode - Return true if the addressing mode represented
2567 /// by AM is legal for this target, for a load/store of the specified type.
2568 bool TargetLowering::isLegalAddressingMode(const AddrMode &AM,
2569 const Type *Ty) const {
2570 // The default implementation of this implements a conservative RISCy, r+r and
2573 // Allows a sign-extended 16-bit immediate field.
2574 if (AM.BaseOffs <= -(1LL << 16) || AM.BaseOffs >= (1LL << 16)-1)
2577 // No global is ever allowed as a base.
2581 // Only support r+r,
2583 case 0: // "r+i" or just "i", depending on HasBaseReg.
2586 if (AM.HasBaseReg && AM.BaseOffs) // "r+r+i" is not allowed.
2588 // Otherwise we have r+r or r+i.
2591 if (AM.HasBaseReg || AM.BaseOffs) // 2*r+r or 2*r+i is not allowed.
2593 // Allow 2*r as r+r.
2600 /// BuildSDIVSequence - Given an ISD::SDIV node expressing a divide by constant,
2601 /// return a DAG expression to select that will generate the same value by
2602 /// multiplying by a magic number. See:
2603 /// <http://the.wall.riscom.net/books/proc/ppc/cwg/code2.html>
2604 SDValue TargetLowering::BuildSDIV(SDNode *N, SelectionDAG &DAG,
2605 std::vector<SDNode*>* Created) const {
2606 EVT VT = N->getValueType(0);
2607 DebugLoc dl= N->getDebugLoc();
2609 // Check to see if we can do this.
2610 // FIXME: We should be more aggressive here.
2611 if (!isTypeLegal(VT))
2614 APInt d = cast<ConstantSDNode>(N->getOperand(1))->getAPIntValue();
2615 APInt::ms magics = d.magic();
2617 // Multiply the numerator (operand 0) by the magic value
2618 // FIXME: We should support doing a MUL in a wider type
2620 if (isOperationLegalOrCustom(ISD::MULHS, VT))
2621 Q = DAG.getNode(ISD::MULHS, dl, VT, N->getOperand(0),
2622 DAG.getConstant(magics.m, VT));
2623 else if (isOperationLegalOrCustom(ISD::SMUL_LOHI, VT))
2624 Q = SDValue(DAG.getNode(ISD::SMUL_LOHI, dl, DAG.getVTList(VT, VT),
2626 DAG.getConstant(magics.m, VT)).getNode(), 1);
2628 return SDValue(); // No mulhs or equvialent
2629 // If d > 0 and m < 0, add the numerator
2630 if (d.isStrictlyPositive() && magics.m.isNegative()) {
2631 Q = DAG.getNode(ISD::ADD, dl, VT, Q, N->getOperand(0));
2633 Created->push_back(Q.getNode());
2635 // If d < 0 and m > 0, subtract the numerator.
2636 if (d.isNegative() && magics.m.isStrictlyPositive()) {
2637 Q = DAG.getNode(ISD::SUB, dl, VT, Q, N->getOperand(0));
2639 Created->push_back(Q.getNode());
2641 // Shift right algebraic if shift value is nonzero
2643 Q = DAG.getNode(ISD::SRA, dl, VT, Q,
2644 DAG.getConstant(magics.s, getShiftAmountTy()));
2646 Created->push_back(Q.getNode());
2648 // Extract the sign bit and add it to the quotient
2650 DAG.getNode(ISD::SRL, dl, VT, Q, DAG.getConstant(VT.getSizeInBits()-1,
2651 getShiftAmountTy()));
2653 Created->push_back(T.getNode());
2654 return DAG.getNode(ISD::ADD, dl, VT, Q, T);
2657 /// BuildUDIVSequence - Given an ISD::UDIV node expressing a divide by constant,
2658 /// return a DAG expression to select that will generate the same value by
2659 /// multiplying by a magic number. See:
2660 /// <http://the.wall.riscom.net/books/proc/ppc/cwg/code2.html>
2661 SDValue TargetLowering::BuildUDIV(SDNode *N, SelectionDAG &DAG,
2662 std::vector<SDNode*>* Created) const {
2663 EVT VT = N->getValueType(0);
2664 DebugLoc dl = N->getDebugLoc();
2666 // Check to see if we can do this.
2667 // FIXME: We should be more aggressive here.
2668 if (!isTypeLegal(VT))
2671 // FIXME: We should use a narrower constant when the upper
2672 // bits are known to be zero.
2673 ConstantSDNode *N1C = cast<ConstantSDNode>(N->getOperand(1));
2674 APInt::mu magics = N1C->getAPIntValue().magicu();
2676 // Multiply the numerator (operand 0) by the magic value
2677 // FIXME: We should support doing a MUL in a wider type
2679 if (isOperationLegalOrCustom(ISD::MULHU, VT))
2680 Q = DAG.getNode(ISD::MULHU, dl, VT, N->getOperand(0),
2681 DAG.getConstant(magics.m, VT));
2682 else if (isOperationLegalOrCustom(ISD::UMUL_LOHI, VT))
2683 Q = SDValue(DAG.getNode(ISD::UMUL_LOHI, dl, DAG.getVTList(VT, VT),
2685 DAG.getConstant(magics.m, VT)).getNode(), 1);
2687 return SDValue(); // No mulhu or equvialent
2689 Created->push_back(Q.getNode());
2691 if (magics.a == 0) {
2692 assert(magics.s < N1C->getAPIntValue().getBitWidth() &&
2693 "We shouldn't generate an undefined shift!");
2694 return DAG.getNode(ISD::SRL, dl, VT, Q,
2695 DAG.getConstant(magics.s, getShiftAmountTy()));
2697 SDValue NPQ = DAG.getNode(ISD::SUB, dl, VT, N->getOperand(0), Q);
2699 Created->push_back(NPQ.getNode());
2700 NPQ = DAG.getNode(ISD::SRL, dl, VT, NPQ,
2701 DAG.getConstant(1, getShiftAmountTy()));
2703 Created->push_back(NPQ.getNode());
2704 NPQ = DAG.getNode(ISD::ADD, dl, VT, NPQ, Q);
2706 Created->push_back(NPQ.getNode());
2707 return DAG.getNode(ISD::SRL, dl, VT, NPQ,
2708 DAG.getConstant(magics.s-1, getShiftAmountTy()));