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 const char *const llvm::x86_asm_table[] = {
40 X86DarwinTargetAsmInfo::X86DarwinTargetAsmInfo(const X86TargetMachine &TM):
41 X86TargetAsmInfo<DarwinTargetAsmInfo>(TM) {
42 const X86Subtarget* Subtarget = &DTM->getSubtarget<X86Subtarget>();
43 bool is64Bit = Subtarget->is64Bit();
45 AlignmentIsInBytes = false;
46 TextAlignFillValue = 0x90;
49 Data64bitsDirective = 0; // we can't emit a 64-bit unit
50 ZeroDirective = "\t.space\t"; // ".space N" emits N zeros.
51 PrivateGlobalPrefix = "L"; // Marker for constant pool idxs
52 LessPrivateGlobalPrefix = "l"; // Marker for some ObjC metadata
53 BSSSection = 0; // no BSS section.
54 ZeroFillDirective = "\t.zerofill\t"; // Uses .zerofill
55 if (DTM->getRelocationModel() != Reloc::Static)
56 ConstantPoolSection = "\t.const_data";
58 ConstantPoolSection = "\t.const\n";
59 JumpTableDataSection = "\t.const\n";
60 CStringSection = "\t.cstring";
61 // FIXME: Why don't always use this section?
63 SixteenByteConstantSection = getUnnamedSection("\t.literal16\n",
64 SectionFlags::Mergeable);
66 LCOMMDirective = "\t.lcomm\t";
67 SwitchToSectionDirective = "\t.section ";
68 StringConstantPrefix = "\1LC";
69 // Leopard and above support aligned common symbols.
70 COMMDirectiveTakesAlignment = (Subtarget->getDarwinVers() >= 9);
71 HasDotTypeDotSizeDirective = false;
72 if (TM.getRelocationModel() == Reloc::Static) {
73 StaticCtorsSection = ".constructor";
74 StaticDtorsSection = ".destructor";
76 StaticCtorsSection = ".mod_init_func";
77 StaticDtorsSection = ".mod_term_func";
80 PersonalityPrefix = "";
81 PersonalitySuffix = "+4@GOTPCREL";
83 PersonalityPrefix = "L";
84 PersonalitySuffix = "$non_lazy_ptr";
86 NeedsIndirectEncoding = true;
87 InlineAsmStart = "## InlineAsm Start";
88 InlineAsmEnd = "## InlineAsm End";
90 SetDirective = "\t.set";
92 UsedDirective = "\t.no_dead_strip\t";
93 WeakDefDirective = "\t.weak_definition ";
94 WeakRefDirective = "\t.weak_reference ";
95 HiddenDirective = "\t.private_extern ";
96 ProtectedDirective = "\t.globl\t";
98 // In non-PIC modes, emit a special label before jump tables so that the
99 // linker can perform more accurate dead code stripping.
100 if (TM.getRelocationModel() != Reloc::PIC_) {
101 // Emit a local label that is preserved until the linker runs.
102 JumpTableSpecialLabelPrefix = "l";
105 SupportsDebugInformation = true;
107 DwarfAbbrevSection = ".section __DWARF,__debug_abbrev,regular,debug";
108 DwarfInfoSection = ".section __DWARF,__debug_info,regular,debug";
109 DwarfLineSection = ".section __DWARF,__debug_line,regular,debug";
110 DwarfFrameSection = ".section __DWARF,__debug_frame,regular,debug";
111 DwarfPubNamesSection = ".section __DWARF,__debug_pubnames,regular,debug";
112 DwarfPubTypesSection = ".section __DWARF,__debug_pubtypes,regular,debug";
113 DwarfStrSection = ".section __DWARF,__debug_str,regular,debug";
114 DwarfLocSection = ".section __DWARF,__debug_loc,regular,debug";
115 DwarfARangesSection = ".section __DWARF,__debug_aranges,regular,debug";
116 DwarfRangesSection = ".section __DWARF,__debug_ranges,regular,debug";
117 DwarfMacInfoSection = ".section __DWARF,__debug_macinfo,regular,debug";
119 // Exceptions handling
120 SupportsExceptionHandling = true;
121 GlobalEHDirective = "\t.globl\t";
122 SupportsWeakOmittedEHFrame = false;
123 AbsoluteEHSectionOffsets = false;
124 DwarfEHFrameSection =
125 ".section __TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support";
126 DwarfExceptionSection = ".section __DATA,__gcc_except_tab";
130 X86DarwinTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
132 if (Reason == DwarfEncoding::Functions && Global)
133 return (DW_EH_PE_pcrel | DW_EH_PE_indirect | DW_EH_PE_sdata4);
134 else if (Reason == DwarfEncoding::CodeLabels || !Global)
135 return DW_EH_PE_pcrel;
137 return DW_EH_PE_absptr;
140 X86ELFTargetAsmInfo::X86ELFTargetAsmInfo(const X86TargetMachine &TM):
141 X86TargetAsmInfo<ELFTargetAsmInfo>(TM) {
143 CStringSection = ".rodata.str";
144 PrivateGlobalPrefix = ".L";
145 WeakRefDirective = "\t.weak\t";
146 SetDirective = "\t.set\t";
149 // Set up DWARF directives
150 HasLEB128 = true; // Target asm supports leb128 directives (little-endian)
153 AbsoluteDebugSectionOffsets = true;
154 SupportsDebugInformation = true;
155 DwarfAbbrevSection = "\t.section\t.debug_abbrev,\"\",@progbits";
156 DwarfInfoSection = "\t.section\t.debug_info,\"\",@progbits";
157 DwarfLineSection = "\t.section\t.debug_line,\"\",@progbits";
158 DwarfFrameSection = "\t.section\t.debug_frame,\"\",@progbits";
159 DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"\",@progbits";
160 DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"\",@progbits";
161 DwarfStrSection = "\t.section\t.debug_str,\"\",@progbits";
162 DwarfLocSection = "\t.section\t.debug_loc,\"\",@progbits";
163 DwarfARangesSection = "\t.section\t.debug_aranges,\"\",@progbits";
164 DwarfRangesSection = "\t.section\t.debug_ranges,\"\",@progbits";
165 DwarfMacInfoSection = "\t.section\t.debug_macinfo,\"\",@progbits";
167 // Exceptions handling
168 SupportsExceptionHandling = true;
169 AbsoluteEHSectionOffsets = false;
170 DwarfEHFrameSection = "\t.section\t.eh_frame,\"aw\",@progbits";
171 DwarfExceptionSection = "\t.section\t.gcc_except_table,\"a\",@progbits";
173 // On Linux we must declare when we can use a non-executable stack.
174 if (ETM->getSubtarget<X86Subtarget>().isLinux())
175 NonexecutableStackDirective = "\t.section\t.note.GNU-stack,\"\",@progbits";
179 X86ELFTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
181 CodeModel::Model CM = ETM->getCodeModel();
182 bool is64Bit = ETM->getSubtarget<X86Subtarget>().is64Bit();
184 if (ETM->getRelocationModel() == Reloc::PIC_) {
188 // 32 bit targets always encode pointers as 4 bytes
189 Format = DW_EH_PE_sdata4;
191 // 64 bit targets encode pointers in 4 bytes iff:
192 // - code model is small OR
193 // - code model is medium and we're emitting externally visible symbols
194 // or any code symbols
195 if (CM == CodeModel::Small ||
196 (CM == CodeModel::Medium && (Global ||
197 Reason != DwarfEncoding::Data)))
198 Format = DW_EH_PE_sdata4;
200 Format = DW_EH_PE_sdata8;
204 Format |= DW_EH_PE_indirect;
206 return (Format | DW_EH_PE_pcrel);
209 (CM == CodeModel::Small ||
210 (CM == CodeModel::Medium && Reason != DwarfEncoding::Data)))
211 return DW_EH_PE_udata4;
213 return DW_EH_PE_absptr;
217 X86COFFTargetAsmInfo::X86COFFTargetAsmInfo(const X86TargetMachine &TM):
218 X86GenericTargetAsmInfo(TM) {
222 LCOMMDirective = "\t.lcomm\t";
223 COMMDirectiveTakesAlignment = false;
224 HasDotTypeDotSizeDirective = false;
225 StaticCtorsSection = "\t.section .ctors,\"aw\"";
226 StaticDtorsSection = "\t.section .dtors,\"aw\"";
227 HiddenDirective = NULL;
228 PrivateGlobalPrefix = "L"; // Prefix for private global symbols
229 WeakRefDirective = "\t.weak\t";
230 SetDirective = "\t.set\t";
232 // Set up DWARF directives
233 HasLEB128 = true; // Target asm supports leb128 directives (little-endian)
234 AbsoluteDebugSectionOffsets = true;
235 AbsoluteEHSectionOffsets = false;
236 SupportsDebugInformation = true;
237 DwarfSectionOffsetDirective = "\t.secrel32\t";
238 DwarfAbbrevSection = "\t.section\t.debug_abbrev,\"dr\"";
239 DwarfInfoSection = "\t.section\t.debug_info,\"dr\"";
240 DwarfLineSection = "\t.section\t.debug_line,\"dr\"";
241 DwarfFrameSection = "\t.section\t.debug_frame,\"dr\"";
242 DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"dr\"";
243 DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"dr\"";
244 DwarfStrSection = "\t.section\t.debug_str,\"dr\"";
245 DwarfLocSection = "\t.section\t.debug_loc,\"dr\"";
246 DwarfARangesSection = "\t.section\t.debug_aranges,\"dr\"";
247 DwarfRangesSection = "\t.section\t.debug_ranges,\"dr\"";
248 DwarfMacInfoSection = "\t.section\t.debug_macinfo,\"dr\"";
252 X86COFFTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
254 CodeModel::Model CM = X86TM->getCodeModel();
255 bool is64Bit = X86TM->getSubtarget<X86Subtarget>().is64Bit();
257 if (X86TM->getRelocationModel() == Reloc::PIC_) {
261 // 32 bit targets always encode pointers as 4 bytes
262 Format = DW_EH_PE_sdata4;
264 // 64 bit targets encode pointers in 4 bytes iff:
265 // - code model is small OR
266 // - code model is medium and we're emitting externally visible symbols
267 // or any code symbols
268 if (CM == CodeModel::Small ||
269 (CM == CodeModel::Medium && (Global ||
270 Reason != DwarfEncoding::Data)))
271 Format = DW_EH_PE_sdata4;
273 Format = DW_EH_PE_sdata8;
277 Format |= DW_EH_PE_indirect;
279 return (Format | DW_EH_PE_pcrel);
282 (CM == CodeModel::Small ||
283 (CM == CodeModel::Medium && Reason != DwarfEncoding::Data)))
284 return DW_EH_PE_udata4;
286 return DW_EH_PE_absptr;
291 X86COFFTargetAsmInfo::UniqueSectionForGlobal(const GlobalValue* GV,
292 SectionKind::Kind kind) const {
294 case SectionKind::Text:
295 return ".text$linkonce" + GV->getName();
296 case SectionKind::Data:
297 case SectionKind::BSS:
298 case SectionKind::ThreadData:
299 case SectionKind::ThreadBSS:
300 return ".data$linkonce" + GV->getName();
301 case SectionKind::ROData:
302 case SectionKind::RODataMergeConst:
303 case SectionKind::RODataMergeStr:
304 return ".rdata$linkonce" + GV->getName();
306 assert(0 && "Unknown section kind");
310 std::string X86COFFTargetAsmInfo::printSectionFlags(unsigned flags) const {
311 std::string Flags = ",\"";
313 if (flags & SectionFlags::Code)
315 if (flags & SectionFlags::Writeable)
323 X86WinTargetAsmInfo::X86WinTargetAsmInfo(const X86TargetMachine &TM):
324 X86GenericTargetAsmInfo(TM) {
328 PrivateGlobalPrefix = "$";
329 AlignDirective = "\talign\t";
330 ZeroDirective = "\tdb\t";
331 ZeroDirectiveSuffix = " dup(0)";
332 AsciiDirective = "\tdb\t";
334 Data8bitsDirective = "\tdb\t";
335 Data16bitsDirective = "\tdw\t";
336 Data32bitsDirective = "\tdd\t";
337 Data64bitsDirective = "\tdq\t";
338 HasDotTypeDotSizeDirective = false;
340 TextSection = getUnnamedSection("_text", SectionFlags::Code);
341 DataSection = getUnnamedSection("_data", SectionFlags::Writeable);
343 JumpTableDataSection = NULL;
344 SwitchToSectionDirective = "";
345 TextSectionStartSuffix = "\tsegment 'CODE'";
346 DataSectionStartSuffix = "\tsegment 'DATA'";
347 SectionEndDirectiveSuffix = "\tends\n";
350 template <class BaseTAI>
351 bool X86TargetAsmInfo<BaseTAI>::LowerToBSwap(CallInst *CI) const {
352 // FIXME: this should verify that we are targetting a 486 or better. If not,
353 // we will turn this bswap into something that will be lowered to logical ops
354 // instead of emitting the bswap asm. For now, we don't support 486 or lower
355 // so don't worry about this.
357 // Verify this is a simple bswap.
358 if (CI->getNumOperands() != 2 ||
359 CI->getType() != CI->getOperand(1)->getType() ||
360 !CI->getType()->isInteger())
363 const IntegerType *Ty = dyn_cast<IntegerType>(CI->getType());
364 if (!Ty || Ty->getBitWidth() % 16 != 0)
367 // Okay, we can do this xform, do so now.
368 const Type *Tys[] = { Ty };
369 Module *M = CI->getParent()->getParent()->getParent();
370 Constant *Int = Intrinsic::getDeclaration(M, Intrinsic::bswap, Tys, 1);
372 Value *Op = CI->getOperand(1);
373 Op = CallInst::Create(Int, Op, CI->getName(), CI);
375 CI->replaceAllUsesWith(Op);
376 CI->eraseFromParent();
380 template <class BaseTAI>
381 bool X86TargetAsmInfo<BaseTAI>::ExpandInlineAsm(CallInst *CI) const {
382 InlineAsm *IA = cast<InlineAsm>(CI->getCalledValue());
383 std::vector<InlineAsm::ConstraintInfo> Constraints = IA->ParseConstraints();
385 std::string AsmStr = IA->getAsmString();
387 // TODO: should remove alternatives from the asmstring: "foo {a|b}" -> "foo a"
388 std::vector<std::string> AsmPieces;
389 SplitString(AsmStr, AsmPieces, "\n"); // ; as separator?
391 switch (AsmPieces.size()) {
392 default: return false;
394 AsmStr = AsmPieces[0];
396 SplitString(AsmStr, AsmPieces, " \t"); // Split with whitespace.
399 if (AsmPieces.size() == 2 &&
400 AsmPieces[0] == "bswap" && AsmPieces[1] == "$0") {
401 // No need to check constraints, nothing other than the equivalent of
402 // "=r,0" would be valid here.
403 return LowerToBSwap(CI);
407 if (CI->getType() == Type::Int64Ty && Constraints.size() >= 2 &&
408 Constraints[0].Codes.size() == 1 && Constraints[0].Codes[0] == "A" &&
409 Constraints[1].Codes.size() == 1 && Constraints[1].Codes[0] == "0") {
410 // bswap %eax / bswap %edx / xchgl %eax, %edx -> llvm.bswap.i64
411 std::vector<std::string> Words;
412 SplitString(AsmPieces[0], Words, " \t");
413 if (Words.size() == 2 && Words[0] == "bswap" && Words[1] == "%eax") {
415 SplitString(AsmPieces[1], Words, " \t");
416 if (Words.size() == 2 && Words[0] == "bswap" && Words[1] == "%edx") {
418 SplitString(AsmPieces[2], Words, " \t,");
419 if (Words.size() == 3 && Words[0] == "xchgl" && Words[1] == "%eax" &&
420 Words[2] == "%edx") {
421 return LowerToBSwap(CI);
431 // Instantiate default implementation.
432 TEMPLATE_INSTANTIATION(class X86TargetAsmInfo<TargetAsmInfo>);