1 //===-- X86TargetAsmInfo.cpp - X86 asm properties ---------------*- C++ -*-===//
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 file contains the declarations of the X86TargetAsmInfo properties.
12 //===----------------------------------------------------------------------===//
14 #include "X86TargetAsmInfo.h"
15 #include "X86TargetMachine.h"
16 #include "X86Subtarget.h"
17 #include "llvm/DerivedTypes.h"
18 #include "llvm/InlineAsm.h"
19 #include "llvm/Instructions.h"
20 #include "llvm/Intrinsics.h"
21 #include "llvm/Module.h"
22 #include "llvm/ADT/StringExtras.h"
23 #include "llvm/Support/Dwarf.h"
26 using namespace llvm::dwarf;
28 static const char *const x86_asm_table[] = {
40 X86TargetAsmInfo::X86TargetAsmInfo(const X86TargetMachine &TM) {
41 const X86Subtarget *Subtarget = &TM.getSubtarget<X86Subtarget>();
43 AsmTransCBE = x86_asm_table;
45 AssemblerDialect = Subtarget->getAsmFlavor();
48 bool X86TargetAsmInfo::LowerToBSwap(CallInst *CI) const {
49 // FIXME: this should verify that we are targetting a 486 or better. If not,
50 // we will turn this bswap into something that will be lowered to logical ops
51 // instead of emitting the bswap asm. For now, we don't support 486 or lower
52 // so don't worry about this.
54 // Verify this is a simple bswap.
55 if (CI->getNumOperands() != 2 ||
56 CI->getType() != CI->getOperand(1)->getType() ||
57 !CI->getType()->isInteger())
60 const IntegerType *Ty = dyn_cast<IntegerType>(CI->getType());
61 if (!Ty || Ty->getBitWidth() % 16 != 0)
64 // Okay, we can do this xform, do so now.
65 const Type *Tys[] = { Ty };
66 Module *M = CI->getParent()->getParent()->getParent();
67 Constant *Int = Intrinsic::getDeclaration(M, Intrinsic::bswap, Tys, 1);
69 Value *Op = CI->getOperand(1);
70 Op = CallInst::Create(Int, Op, CI->getName(), CI);
72 CI->replaceAllUsesWith(Op);
73 CI->eraseFromParent();
77 bool X86TargetAsmInfo::ExpandInlineAsm(CallInst *CI) const {
78 InlineAsm *IA = cast<InlineAsm>(CI->getCalledValue());
79 std::vector<InlineAsm::ConstraintInfo> Constraints = IA->ParseConstraints();
81 std::string AsmStr = IA->getAsmString();
83 // TODO: should remove alternatives from the asmstring: "foo {a|b}" -> "foo a"
84 std::vector<std::string> AsmPieces;
85 SplitString(AsmStr, AsmPieces, "\n"); // ; as separator?
87 switch (AsmPieces.size()) {
88 default: return false;
90 AsmStr = AsmPieces[0];
92 SplitString(AsmStr, AsmPieces, " \t"); // Split with whitespace.
95 if (AsmPieces.size() == 2 &&
96 AsmPieces[0] == "bswap" && AsmPieces[1] == "$0") {
97 // No need to check constraints, nothing other than the equivalent of
98 // "=r,0" would be valid here.
99 return LowerToBSwap(CI);
103 if (CI->getType() == Type::Int64Ty && Constraints.size() >= 2 &&
104 Constraints[0].Codes.size() == 1 && Constraints[0].Codes[0] == "A" &&
105 Constraints[1].Codes.size() == 1 && Constraints[1].Codes[0] == "0") {
106 // bswap %eax / bswap %edx / xchgl %eax, %edx -> llvm.bswap.i64
107 std::vector<std::string> Words;
108 SplitString(AsmPieces[0], Words, " \t");
109 if (Words.size() == 2 && Words[0] == "bswap" && Words[1] == "%eax") {
111 SplitString(AsmPieces[1], Words, " \t");
112 if (Words.size() == 2 && Words[0] == "bswap" && Words[1] == "%edx") {
114 SplitString(AsmPieces[2], Words, " \t,");
115 if (Words.size() == 3 && Words[0] == "xchgl" && Words[1] == "%eax" &&
116 Words[2] == "%edx") {
117 return LowerToBSwap(CI);
127 X86DarwinTargetAsmInfo::X86DarwinTargetAsmInfo(const X86TargetMachine &TM):
128 X86TargetAsmInfo(TM), DarwinTargetAsmInfo(TM) {
129 const X86Subtarget* Subtarget = &DTM->getSubtarget<X86Subtarget>();
130 bool is64Bit = Subtarget->is64Bit();
132 AlignmentIsInBytes = false;
133 TextAlignFillValue = 0x90;
136 Data64bitsDirective = 0; // we can't emit a 64-bit unit
137 ZeroDirective = "\t.space\t"; // ".space N" emits N zeros.
138 PrivateGlobalPrefix = "L"; // Marker for constant pool idxs
139 LessPrivateGlobalPrefix = "l"; // Marker for some ObjC metadata
140 BSSSection = 0; // no BSS section.
141 ZeroFillDirective = "\t.zerofill\t"; // Uses .zerofill
142 if (DTM->getRelocationModel() != Reloc::Static)
143 ConstantPoolSection = "\t.const_data";
145 ConstantPoolSection = "\t.const\n";
146 JumpTableDataSection = "\t.const\n";
147 CStringSection = "\t.cstring";
148 // FIXME: Why don't always use this section?
150 SixteenByteConstantSection = getUnnamedSection("\t.literal16\n",
151 SectionFlags::Mergeable);
153 LCOMMDirective = "\t.lcomm\t";
154 SwitchToSectionDirective = "\t.section ";
155 StringConstantPrefix = "\1LC";
156 // Leopard and above support aligned common symbols.
157 COMMDirectiveTakesAlignment = (Subtarget->getDarwinVers() >= 9);
158 HasDotTypeDotSizeDirective = false;
159 if (TM.getRelocationModel() == Reloc::Static) {
160 StaticCtorsSection = ".constructor";
161 StaticDtorsSection = ".destructor";
163 StaticCtorsSection = ".mod_init_func";
164 StaticDtorsSection = ".mod_term_func";
167 PersonalityPrefix = "";
168 PersonalitySuffix = "+4@GOTPCREL";
170 PersonalityPrefix = "L";
171 PersonalitySuffix = "$non_lazy_ptr";
173 NeedsIndirectEncoding = true;
174 InlineAsmStart = "## InlineAsm Start";
175 InlineAsmEnd = "## InlineAsm End";
176 CommentString = "##";
177 SetDirective = "\t.set";
179 UsedDirective = "\t.no_dead_strip\t";
180 WeakDefDirective = "\t.weak_definition ";
181 WeakRefDirective = "\t.weak_reference ";
182 HiddenDirective = "\t.private_extern ";
183 ProtectedDirective = "\t.globl\t";
185 // In non-PIC modes, emit a special label before jump tables so that the
186 // linker can perform more accurate dead code stripping.
187 if (TM.getRelocationModel() != Reloc::PIC_) {
188 // Emit a local label that is preserved until the linker runs.
189 JumpTableSpecialLabelPrefix = "l";
192 SupportsDebugInformation = true;
194 DwarfAbbrevSection = ".section __DWARF,__debug_abbrev,regular,debug";
195 DwarfInfoSection = ".section __DWARF,__debug_info,regular,debug";
196 DwarfLineSection = ".section __DWARF,__debug_line,regular,debug";
197 DwarfFrameSection = ".section __DWARF,__debug_frame,regular,debug";
198 DwarfPubNamesSection = ".section __DWARF,__debug_pubnames,regular,debug";
199 DwarfPubTypesSection = ".section __DWARF,__debug_pubtypes,regular,debug";
200 DwarfStrSection = ".section __DWARF,__debug_str,regular,debug";
201 DwarfLocSection = ".section __DWARF,__debug_loc,regular,debug";
202 DwarfARangesSection = ".section __DWARF,__debug_aranges,regular,debug";
203 DwarfRangesSection = ".section __DWARF,__debug_ranges,regular,debug";
204 DwarfMacInfoSection = ".section __DWARF,__debug_macinfo,regular,debug";
206 // Exceptions handling
207 SupportsExceptionHandling = true;
208 GlobalEHDirective = "\t.globl\t";
209 SupportsWeakOmittedEHFrame = false;
210 AbsoluteEHSectionOffsets = false;
211 DwarfEHFrameSection =
212 ".section __TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support";
213 DwarfExceptionSection = ".section __DATA,__gcc_except_tab";
217 X86DarwinTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
219 if (Reason == DwarfEncoding::Functions && Global)
220 return (DW_EH_PE_pcrel | DW_EH_PE_indirect | DW_EH_PE_sdata4);
221 else if (Reason == DwarfEncoding::CodeLabels || !Global)
222 return DW_EH_PE_pcrel;
224 return DW_EH_PE_absptr;
227 X86ELFTargetAsmInfo::X86ELFTargetAsmInfo(const X86TargetMachine &TM):
228 X86TargetAsmInfo(TM), ELFTargetAsmInfo(TM) {
230 CStringSection = ".rodata.str";
231 PrivateGlobalPrefix = ".L";
232 WeakRefDirective = "\t.weak\t";
233 SetDirective = "\t.set\t";
236 // Set up DWARF directives
237 HasLEB128 = true; // Target asm supports leb128 directives (little-endian)
240 AbsoluteDebugSectionOffsets = true;
241 SupportsDebugInformation = true;
242 DwarfAbbrevSection = "\t.section\t.debug_abbrev,\"\",@progbits";
243 DwarfInfoSection = "\t.section\t.debug_info,\"\",@progbits";
244 DwarfLineSection = "\t.section\t.debug_line,\"\",@progbits";
245 DwarfFrameSection = "\t.section\t.debug_frame,\"\",@progbits";
246 DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"\",@progbits";
247 DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"\",@progbits";
248 DwarfStrSection = "\t.section\t.debug_str,\"\",@progbits";
249 DwarfLocSection = "\t.section\t.debug_loc,\"\",@progbits";
250 DwarfARangesSection = "\t.section\t.debug_aranges,\"\",@progbits";
251 DwarfRangesSection = "\t.section\t.debug_ranges,\"\",@progbits";
252 DwarfMacInfoSection = "\t.section\t.debug_macinfo,\"\",@progbits";
254 // Exceptions handling
255 SupportsExceptionHandling = true;
256 AbsoluteEHSectionOffsets = false;
257 DwarfEHFrameSection = "\t.section\t.eh_frame,\"aw\",@progbits";
258 DwarfExceptionSection = "\t.section\t.gcc_except_table,\"a\",@progbits";
260 // On Linux we must declare when we can use a non-executable stack.
261 if (ETM->getSubtarget<X86Subtarget>().isLinux())
262 NonexecutableStackDirective = "\t.section\t.note.GNU-stack,\"\",@progbits";
266 X86ELFTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
268 CodeModel::Model CM = ETM->getCodeModel();
269 bool is64Bit = ETM->getSubtarget<X86Subtarget>().is64Bit();
271 if (ETM->getRelocationModel() == Reloc::PIC_) {
275 // 32 bit targets always encode pointers as 4 bytes
276 Format = DW_EH_PE_sdata4;
278 // 64 bit targets encode pointers in 4 bytes iff:
279 // - code model is small OR
280 // - code model is medium and we're emitting externally visible symbols
281 // or any code symbols
282 if (CM == CodeModel::Small ||
283 (CM == CodeModel::Medium && (Global ||
284 Reason != DwarfEncoding::Data)))
285 Format = DW_EH_PE_sdata4;
287 Format = DW_EH_PE_sdata8;
291 Format |= DW_EH_PE_indirect;
293 return (Format | DW_EH_PE_pcrel);
296 (CM == CodeModel::Small ||
297 (CM == CodeModel::Medium && Reason != DwarfEncoding::Data)))
298 return DW_EH_PE_udata4;
300 return DW_EH_PE_absptr;
304 X86COFFTargetAsmInfo::X86COFFTargetAsmInfo(const X86TargetMachine &TM):
305 X86TargetAsmInfo(TM) {
309 LCOMMDirective = "\t.lcomm\t";
310 COMMDirectiveTakesAlignment = false;
311 HasDotTypeDotSizeDirective = false;
312 StaticCtorsSection = "\t.section .ctors,\"aw\"";
313 StaticDtorsSection = "\t.section .dtors,\"aw\"";
314 HiddenDirective = NULL;
315 PrivateGlobalPrefix = "L"; // Prefix for private global symbols
316 WeakRefDirective = "\t.weak\t";
317 SetDirective = "\t.set\t";
319 // Set up DWARF directives
320 HasLEB128 = true; // Target asm supports leb128 directives (little-endian)
321 AbsoluteDebugSectionOffsets = true;
322 AbsoluteEHSectionOffsets = false;
323 SupportsDebugInformation = true;
324 DwarfSectionOffsetDirective = "\t.secrel32\t";
325 DwarfAbbrevSection = "\t.section\t.debug_abbrev,\"dr\"";
326 DwarfInfoSection = "\t.section\t.debug_info,\"dr\"";
327 DwarfLineSection = "\t.section\t.debug_line,\"dr\"";
328 DwarfFrameSection = "\t.section\t.debug_frame,\"dr\"";
329 DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"dr\"";
330 DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"dr\"";
331 DwarfStrSection = "\t.section\t.debug_str,\"dr\"";
332 DwarfLocSection = "\t.section\t.debug_loc,\"dr\"";
333 DwarfARangesSection = "\t.section\t.debug_aranges,\"dr\"";
334 DwarfRangesSection = "\t.section\t.debug_ranges,\"dr\"";
335 DwarfMacInfoSection = "\t.section\t.debug_macinfo,\"dr\"";
339 X86COFFTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
341 CodeModel::Model CM = X86TM->getCodeModel();
342 bool is64Bit = X86TM->getSubtarget<X86Subtarget>().is64Bit();
344 if (X86TM->getRelocationModel() == Reloc::PIC_) {
348 // 32 bit targets always encode pointers as 4 bytes
349 Format = DW_EH_PE_sdata4;
351 // 64 bit targets encode pointers in 4 bytes iff:
352 // - code model is small OR
353 // - code model is medium and we're emitting externally visible symbols
354 // or any code symbols
355 if (CM == CodeModel::Small ||
356 (CM == CodeModel::Medium && (Global ||
357 Reason != DwarfEncoding::Data)))
358 Format = DW_EH_PE_sdata4;
360 Format = DW_EH_PE_sdata8;
364 Format |= DW_EH_PE_indirect;
366 return (Format | DW_EH_PE_pcrel);
369 (CM == CodeModel::Small ||
370 (CM == CodeModel::Medium && Reason != DwarfEncoding::Data)))
371 return DW_EH_PE_udata4;
373 return DW_EH_PE_absptr;
378 X86COFFTargetAsmInfo::UniqueSectionForGlobal(const GlobalValue* GV,
379 SectionKind::Kind kind) const {
381 case SectionKind::Text:
382 return ".text$linkonce" + GV->getName();
383 case SectionKind::Data:
384 case SectionKind::BSS:
385 case SectionKind::ThreadData:
386 case SectionKind::ThreadBSS:
387 return ".data$linkonce" + GV->getName();
388 case SectionKind::ROData:
389 case SectionKind::RODataMergeConst:
390 case SectionKind::RODataMergeStr:
391 return ".rdata$linkonce" + GV->getName();
393 assert(0 && "Unknown section kind");
397 std::string X86COFFTargetAsmInfo::printSectionFlags(unsigned flags) const {
398 std::string Flags = ",\"";
400 if (flags & SectionFlags::Code)
402 if (flags & SectionFlags::Writeable)
410 X86WinTargetAsmInfo::X86WinTargetAsmInfo(const X86TargetMachine &TM):
411 X86TargetAsmInfo(TM) {
415 PrivateGlobalPrefix = "$";
416 AlignDirective = "\talign\t";
417 ZeroDirective = "\tdb\t";
418 ZeroDirectiveSuffix = " dup(0)";
419 AsciiDirective = "\tdb\t";
421 Data8bitsDirective = "\tdb\t";
422 Data16bitsDirective = "\tdw\t";
423 Data32bitsDirective = "\tdd\t";
424 Data64bitsDirective = "\tdq\t";
425 HasDotTypeDotSizeDirective = false;
427 TextSection = getUnnamedSection("_text", SectionFlags::Code);
428 DataSection = getUnnamedSection("_data", SectionFlags::Writeable);
430 JumpTableDataSection = NULL;
431 SwitchToSectionDirective = "";
432 TextSectionStartSuffix = "\tsegment 'CODE'";
433 DataSectionStartSuffix = "\tsegment 'DATA'";
434 SectionEndDirectiveSuffix = "\tends\n";