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 = &TM.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 (TM.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 HasSingleParameterDotFile = false;
73 NonLocalEHFrameLabel = true;
74 if (TM.getRelocationModel() == Reloc::Static) {
75 StaticCtorsSection = ".constructor";
76 StaticDtorsSection = ".destructor";
78 StaticCtorsSection = ".mod_init_func";
79 StaticDtorsSection = ".mod_term_func";
82 PersonalityPrefix = "";
83 PersonalitySuffix = "+4@GOTPCREL";
85 PersonalityPrefix = "L";
86 PersonalitySuffix = "$non_lazy_ptr";
88 NeedsIndirectEncoding = true;
89 InlineAsmStart = "## InlineAsm Start";
90 InlineAsmEnd = "## InlineAsm End";
92 SetDirective = "\t.set";
94 UsedDirective = "\t.no_dead_strip\t";
95 WeakDefDirective = "\t.weak_definition ";
96 WeakRefDirective = "\t.weak_reference ";
97 HiddenDirective = "\t.private_extern ";
98 ProtectedDirective = "\t.globl\t";
100 // In non-PIC modes, emit a special label before jump tables so that the
101 // linker can perform more accurate dead code stripping.
102 if (TM.getRelocationModel() != Reloc::PIC_) {
103 // Emit a local label that is preserved until the linker runs.
104 JumpTableSpecialLabelPrefix = "l";
107 SupportsDebugInformation = true;
109 DwarfAbbrevSection = ".section __DWARF,__debug_abbrev,regular,debug";
110 DwarfInfoSection = ".section __DWARF,__debug_info,regular,debug";
111 DwarfLineSection = ".section __DWARF,__debug_line,regular,debug";
112 DwarfFrameSection = ".section __DWARF,__debug_frame,regular,debug";
113 DwarfPubNamesSection = ".section __DWARF,__debug_pubnames,regular,debug";
114 DwarfPubTypesSection = ".section __DWARF,__debug_pubtypes,regular,debug";
115 DwarfDebugInlineSection = ".section __DWARF,__debug_inlined,regular,debug";
116 DwarfUsesInlineInfoSection = true;
117 DwarfStrSection = ".section __DWARF,__debug_str,regular,debug";
118 DwarfLocSection = ".section __DWARF,__debug_loc,regular,debug";
119 DwarfARangesSection = ".section __DWARF,__debug_aranges,regular,debug";
120 DwarfRangesSection = ".section __DWARF,__debug_ranges,regular,debug";
121 DwarfMacInfoSection = ".section __DWARF,__debug_macinfo,regular,debug";
123 // Exceptions handling
124 SupportsExceptionHandling = true;
125 GlobalEHDirective = "\t.globl\t";
126 SupportsWeakOmittedEHFrame = false;
127 AbsoluteEHSectionOffsets = false;
128 DwarfEHFrameSection =
129 ".section __TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support";
130 DwarfExceptionSection = ".section __DATA,__gcc_except_tab";
134 X86DarwinTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
136 if (Reason == DwarfEncoding::Functions && Global)
137 return (DW_EH_PE_pcrel | DW_EH_PE_indirect | DW_EH_PE_sdata4);
138 else if (Reason == DwarfEncoding::CodeLabels || !Global)
139 return DW_EH_PE_pcrel;
141 return DW_EH_PE_absptr;
145 X86DarwinTargetAsmInfo::getEHGlobalPrefix() const
147 const X86Subtarget* Subtarget = &TM.getSubtarget<X86Subtarget>();
148 if (Subtarget->getDarwinVers() > 9)
149 return PrivateGlobalPrefix;
154 X86ELFTargetAsmInfo::X86ELFTargetAsmInfo(const X86TargetMachine &TM):
155 X86TargetAsmInfo<ELFTargetAsmInfo>(TM) {
157 CStringSection = ".rodata.str";
158 PrivateGlobalPrefix = ".L";
159 WeakRefDirective = "\t.weak\t";
160 SetDirective = "\t.set\t";
163 // Set up DWARF directives
164 HasLEB128 = true; // Target asm supports leb128 directives (little-endian)
167 AbsoluteDebugSectionOffsets = true;
168 SupportsDebugInformation = true;
169 DwarfAbbrevSection = "\t.section\t.debug_abbrev,\"\",@progbits";
170 DwarfInfoSection = "\t.section\t.debug_info,\"\",@progbits";
171 DwarfLineSection = "\t.section\t.debug_line,\"\",@progbits";
172 DwarfFrameSection = "\t.section\t.debug_frame,\"\",@progbits";
173 DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"\",@progbits";
174 DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"\",@progbits";
175 DwarfStrSection = "\t.section\t.debug_str,\"\",@progbits";
176 DwarfLocSection = "\t.section\t.debug_loc,\"\",@progbits";
177 DwarfARangesSection = "\t.section\t.debug_aranges,\"\",@progbits";
178 DwarfRangesSection = "\t.section\t.debug_ranges,\"\",@progbits";
179 DwarfMacInfoSection = "\t.section\t.debug_macinfo,\"\",@progbits";
181 // Exceptions handling
182 SupportsExceptionHandling = true;
183 AbsoluteEHSectionOffsets = false;
184 DwarfEHFrameSection = "\t.section\t.eh_frame,\"aw\",@progbits";
185 DwarfExceptionSection = "\t.section\t.gcc_except_table,\"a\",@progbits";
187 // On Linux we must declare when we can use a non-executable stack.
188 if (TM.getSubtarget<X86Subtarget>().isLinux())
189 NonexecutableStackDirective = "\t.section\t.note.GNU-stack,\"\",@progbits";
193 X86ELFTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
195 CodeModel::Model CM = TM.getCodeModel();
196 bool is64Bit = TM.getSubtarget<X86Subtarget>().is64Bit();
198 if (TM.getRelocationModel() == Reloc::PIC_) {
202 // 32 bit targets always encode pointers as 4 bytes
203 Format = DW_EH_PE_sdata4;
205 // 64 bit targets encode pointers in 4 bytes iff:
206 // - code model is small OR
207 // - code model is medium and we're emitting externally visible symbols
208 // or any code symbols
209 if (CM == CodeModel::Small ||
210 (CM == CodeModel::Medium && (Global ||
211 Reason != DwarfEncoding::Data)))
212 Format = DW_EH_PE_sdata4;
214 Format = DW_EH_PE_sdata8;
218 Format |= DW_EH_PE_indirect;
220 return (Format | DW_EH_PE_pcrel);
223 (CM == CodeModel::Small ||
224 (CM == CodeModel::Medium && Reason != DwarfEncoding::Data)))
225 return DW_EH_PE_udata4;
227 return DW_EH_PE_absptr;
231 X86COFFTargetAsmInfo::X86COFFTargetAsmInfo(const X86TargetMachine &TM):
232 X86GenericTargetAsmInfo(TM) {
235 LCOMMDirective = "\t.lcomm\t";
236 COMMDirectiveTakesAlignment = false;
237 HasDotTypeDotSizeDirective = false;
238 HasSingleParameterDotFile = false;
239 StaticCtorsSection = "\t.section .ctors,\"aw\"";
240 StaticDtorsSection = "\t.section .dtors,\"aw\"";
241 HiddenDirective = NULL;
242 PrivateGlobalPrefix = "L"; // Prefix for private global symbols
243 WeakRefDirective = "\t.weak\t";
244 SetDirective = "\t.set\t";
246 // Set up DWARF directives
247 HasLEB128 = true; // Target asm supports leb128 directives (little-endian)
248 AbsoluteDebugSectionOffsets = true;
249 AbsoluteEHSectionOffsets = false;
250 SupportsDebugInformation = true;
251 DwarfSectionOffsetDirective = "\t.secrel32\t";
252 DwarfAbbrevSection = "\t.section\t.debug_abbrev,\"dr\"";
253 DwarfInfoSection = "\t.section\t.debug_info,\"dr\"";
254 DwarfLineSection = "\t.section\t.debug_line,\"dr\"";
255 DwarfFrameSection = "\t.section\t.debug_frame,\"dr\"";
256 DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"dr\"";
257 DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"dr\"";
258 DwarfStrSection = "\t.section\t.debug_str,\"dr\"";
259 DwarfLocSection = "\t.section\t.debug_loc,\"dr\"";
260 DwarfARangesSection = "\t.section\t.debug_aranges,\"dr\"";
261 DwarfRangesSection = "\t.section\t.debug_ranges,\"dr\"";
262 DwarfMacInfoSection = "\t.section\t.debug_macinfo,\"dr\"";
266 X86COFFTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
268 CodeModel::Model CM = TM.getCodeModel();
269 bool is64Bit = TM.getSubtarget<X86Subtarget>().is64Bit();
271 if (TM.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;
305 X86COFFTargetAsmInfo::UniqueSectionForGlobal(const GlobalValue* GV,
306 SectionKind::Kind kind) const {
308 case SectionKind::Text:
309 return ".text$linkonce" + GV->getName();
310 case SectionKind::Data:
311 case SectionKind::BSS:
312 case SectionKind::ThreadData:
313 case SectionKind::ThreadBSS:
314 return ".data$linkonce" + GV->getName();
315 case SectionKind::ROData:
316 case SectionKind::RODataMergeConst:
317 case SectionKind::RODataMergeStr:
318 return ".rdata$linkonce" + GV->getName();
320 assert(0 && "Unknown section kind");
325 std::string X86COFFTargetAsmInfo::printSectionFlags(unsigned flags) const {
326 std::string Flags = ",\"";
328 if (flags & SectionFlags::Code)
330 if (flags & SectionFlags::Writeable)
338 X86WinTargetAsmInfo::X86WinTargetAsmInfo(const X86TargetMachine &TM):
339 X86GenericTargetAsmInfo(TM) {
343 PrivateGlobalPrefix = "$";
344 AlignDirective = "\talign\t";
345 ZeroDirective = "\tdb\t";
346 ZeroDirectiveSuffix = " dup(0)";
347 AsciiDirective = "\tdb\t";
349 Data8bitsDirective = "\tdb\t";
350 Data16bitsDirective = "\tdw\t";
351 Data32bitsDirective = "\tdd\t";
352 Data64bitsDirective = "\tdq\t";
353 HasDotTypeDotSizeDirective = false;
354 HasSingleParameterDotFile = false;
356 TextSection = getUnnamedSection("_text", SectionFlags::Code);
357 DataSection = getUnnamedSection("_data", SectionFlags::Writeable);
359 JumpTableDataSection = NULL;
360 SwitchToSectionDirective = "";
361 TextSectionStartSuffix = "\tsegment 'CODE'";
362 DataSectionStartSuffix = "\tsegment 'DATA'";
363 SectionEndDirectiveSuffix = "\tends\n";
366 template <class BaseTAI>
367 bool X86TargetAsmInfo<BaseTAI>::LowerToBSwap(CallInst *CI) const {
368 // FIXME: this should verify that we are targetting a 486 or better. If not,
369 // we will turn this bswap into something that will be lowered to logical ops
370 // instead of emitting the bswap asm. For now, we don't support 486 or lower
371 // so don't worry about this.
373 // Verify this is a simple bswap.
374 if (CI->getNumOperands() != 2 ||
375 CI->getType() != CI->getOperand(1)->getType() ||
376 !CI->getType()->isInteger())
379 const IntegerType *Ty = dyn_cast<IntegerType>(CI->getType());
380 if (!Ty || Ty->getBitWidth() % 16 != 0)
383 // Okay, we can do this xform, do so now.
384 const Type *Tys[] = { Ty };
385 Module *M = CI->getParent()->getParent()->getParent();
386 Constant *Int = Intrinsic::getDeclaration(M, Intrinsic::bswap, Tys, 1);
388 Value *Op = CI->getOperand(1);
389 Op = CallInst::Create(Int, Op, CI->getName(), CI);
391 CI->replaceAllUsesWith(Op);
392 CI->eraseFromParent();
396 template <class BaseTAI>
397 bool X86TargetAsmInfo<BaseTAI>::ExpandInlineAsm(CallInst *CI) const {
398 InlineAsm *IA = cast<InlineAsm>(CI->getCalledValue());
399 std::vector<InlineAsm::ConstraintInfo> Constraints = IA->ParseConstraints();
401 std::string AsmStr = IA->getAsmString();
403 // TODO: should remove alternatives from the asmstring: "foo {a|b}" -> "foo a"
404 std::vector<std::string> AsmPieces;
405 SplitString(AsmStr, AsmPieces, "\n"); // ; as separator?
407 switch (AsmPieces.size()) {
408 default: return false;
410 AsmStr = AsmPieces[0];
412 SplitString(AsmStr, AsmPieces, " \t"); // Split with whitespace.
415 if (AsmPieces.size() == 2 &&
416 (AsmPieces[0] == "bswap" ||
417 AsmPieces[0] == "bswapq" ||
418 AsmPieces[0] == "bswapl") &&
419 (AsmPieces[1] == "$0" ||
420 AsmPieces[1] == "${0:q}")) {
421 // No need to check constraints, nothing other than the equivalent of
422 // "=r,0" would be valid here.
423 return LowerToBSwap(CI);
425 // rorw $$8, ${0:w} --> llvm.bswap.i16
426 if (CI->getType() == Type::Int16Ty &&
427 AsmPieces.size() == 3 &&
428 AsmPieces[0] == "rorw" &&
429 AsmPieces[1] == "$$8," &&
430 AsmPieces[2] == "${0:w}" &&
431 IA->getConstraintString() == "=r,0,~{dirflag},~{fpsr},~{flags},~{cc}") {
432 return LowerToBSwap(CI);
436 if (CI->getType() == Type::Int64Ty && Constraints.size() >= 2 &&
437 Constraints[0].Codes.size() == 1 && Constraints[0].Codes[0] == "A" &&
438 Constraints[1].Codes.size() == 1 && Constraints[1].Codes[0] == "0") {
439 // bswap %eax / bswap %edx / xchgl %eax, %edx -> llvm.bswap.i64
440 std::vector<std::string> Words;
441 SplitString(AsmPieces[0], Words, " \t");
442 if (Words.size() == 2 && Words[0] == "bswap" && Words[1] == "%eax") {
444 SplitString(AsmPieces[1], Words, " \t");
445 if (Words.size() == 2 && Words[0] == "bswap" && Words[1] == "%edx") {
447 SplitString(AsmPieces[2], Words, " \t,");
448 if (Words.size() == 3 && Words[0] == "xchgl" && Words[1] == "%eax" &&
449 Words[2] == "%edx") {
450 return LowerToBSwap(CI);
460 // Instantiate default implementation.
461 TEMPLATE_INSTANTIATION(class X86TargetAsmInfo<TargetAsmInfo>);