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 DwarfStrSection = ".section __DWARF,__debug_str,regular,debug";
116 DwarfLocSection = ".section __DWARF,__debug_loc,regular,debug";
117 DwarfARangesSection = ".section __DWARF,__debug_aranges,regular,debug";
118 DwarfRangesSection = ".section __DWARF,__debug_ranges,regular,debug";
119 DwarfMacInfoSection = ".section __DWARF,__debug_macinfo,regular,debug";
121 // Exceptions handling
122 SupportsExceptionHandling = true;
123 GlobalEHDirective = "\t.globl\t";
124 SupportsWeakOmittedEHFrame = false;
125 AbsoluteEHSectionOffsets = false;
126 DwarfEHFrameSection =
127 ".section __TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support";
128 DwarfExceptionSection = ".section __DATA,__gcc_except_tab";
132 X86DarwinTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
134 if (Reason == DwarfEncoding::Functions && Global)
135 return (DW_EH_PE_pcrel | DW_EH_PE_indirect | DW_EH_PE_sdata4);
136 else if (Reason == DwarfEncoding::CodeLabels || !Global)
137 return DW_EH_PE_pcrel;
139 return DW_EH_PE_absptr;
143 X86DarwinTargetAsmInfo::getEHGlobalPrefix() const
145 const X86Subtarget* Subtarget = &TM.getSubtarget<X86Subtarget>();
146 if (Subtarget->getDarwinVers() > 9)
147 return PrivateGlobalPrefix;
152 X86ELFTargetAsmInfo::X86ELFTargetAsmInfo(const X86TargetMachine &TM):
153 X86TargetAsmInfo<ELFTargetAsmInfo>(TM) {
155 CStringSection = ".rodata.str";
156 PrivateGlobalPrefix = ".L";
157 WeakRefDirective = "\t.weak\t";
158 SetDirective = "\t.set\t";
161 // Set up DWARF directives
162 HasLEB128 = true; // Target asm supports leb128 directives (little-endian)
165 AbsoluteDebugSectionOffsets = true;
166 SupportsDebugInformation = true;
167 DwarfAbbrevSection = "\t.section\t.debug_abbrev,\"\",@progbits";
168 DwarfInfoSection = "\t.section\t.debug_info,\"\",@progbits";
169 DwarfLineSection = "\t.section\t.debug_line,\"\",@progbits";
170 DwarfFrameSection = "\t.section\t.debug_frame,\"\",@progbits";
171 DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"\",@progbits";
172 DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"\",@progbits";
173 DwarfStrSection = "\t.section\t.debug_str,\"\",@progbits";
174 DwarfLocSection = "\t.section\t.debug_loc,\"\",@progbits";
175 DwarfARangesSection = "\t.section\t.debug_aranges,\"\",@progbits";
176 DwarfRangesSection = "\t.section\t.debug_ranges,\"\",@progbits";
177 DwarfMacInfoSection = "\t.section\t.debug_macinfo,\"\",@progbits";
179 // Exceptions handling
180 SupportsExceptionHandling = true;
181 AbsoluteEHSectionOffsets = false;
182 DwarfEHFrameSection = "\t.section\t.eh_frame,\"aw\",@progbits";
183 DwarfExceptionSection = "\t.section\t.gcc_except_table,\"a\",@progbits";
185 // On Linux we must declare when we can use a non-executable stack.
186 if (TM.getSubtarget<X86Subtarget>().isLinux())
187 NonexecutableStackDirective = "\t.section\t.note.GNU-stack,\"\",@progbits";
191 X86ELFTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
193 CodeModel::Model CM = TM.getCodeModel();
194 bool is64Bit = TM.getSubtarget<X86Subtarget>().is64Bit();
196 if (TM.getRelocationModel() == Reloc::PIC_) {
200 // 32 bit targets always encode pointers as 4 bytes
201 Format = DW_EH_PE_sdata4;
203 // 64 bit targets encode pointers in 4 bytes iff:
204 // - code model is small OR
205 // - code model is medium and we're emitting externally visible symbols
206 // or any code symbols
207 if (CM == CodeModel::Small ||
208 (CM == CodeModel::Medium && (Global ||
209 Reason != DwarfEncoding::Data)))
210 Format = DW_EH_PE_sdata4;
212 Format = DW_EH_PE_sdata8;
216 Format |= DW_EH_PE_indirect;
218 return (Format | DW_EH_PE_pcrel);
221 (CM == CodeModel::Small ||
222 (CM == CodeModel::Medium && Reason != DwarfEncoding::Data)))
223 return DW_EH_PE_udata4;
225 return DW_EH_PE_absptr;
229 X86COFFTargetAsmInfo::X86COFFTargetAsmInfo(const X86TargetMachine &TM):
230 X86GenericTargetAsmInfo(TM) {
233 LCOMMDirective = "\t.lcomm\t";
234 COMMDirectiveTakesAlignment = false;
235 HasDotTypeDotSizeDirective = false;
236 HasSingleParameterDotFile = false;
237 StaticCtorsSection = "\t.section .ctors,\"aw\"";
238 StaticDtorsSection = "\t.section .dtors,\"aw\"";
239 HiddenDirective = NULL;
240 PrivateGlobalPrefix = "L"; // Prefix for private global symbols
241 WeakRefDirective = "\t.weak\t";
242 SetDirective = "\t.set\t";
244 // Set up DWARF directives
245 HasLEB128 = true; // Target asm supports leb128 directives (little-endian)
246 AbsoluteDebugSectionOffsets = true;
247 AbsoluteEHSectionOffsets = false;
248 SupportsDebugInformation = true;
249 DwarfSectionOffsetDirective = "\t.secrel32\t";
250 DwarfAbbrevSection = "\t.section\t.debug_abbrev,\"dr\"";
251 DwarfInfoSection = "\t.section\t.debug_info,\"dr\"";
252 DwarfLineSection = "\t.section\t.debug_line,\"dr\"";
253 DwarfFrameSection = "\t.section\t.debug_frame,\"dr\"";
254 DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"dr\"";
255 DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"dr\"";
256 DwarfStrSection = "\t.section\t.debug_str,\"dr\"";
257 DwarfLocSection = "\t.section\t.debug_loc,\"dr\"";
258 DwarfARangesSection = "\t.section\t.debug_aranges,\"dr\"";
259 DwarfRangesSection = "\t.section\t.debug_ranges,\"dr\"";
260 DwarfMacInfoSection = "\t.section\t.debug_macinfo,\"dr\"";
264 X86COFFTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
266 CodeModel::Model CM = TM.getCodeModel();
267 bool is64Bit = TM.getSubtarget<X86Subtarget>().is64Bit();
269 if (TM.getRelocationModel() == Reloc::PIC_) {
273 // 32 bit targets always encode pointers as 4 bytes
274 Format = DW_EH_PE_sdata4;
276 // 64 bit targets encode pointers in 4 bytes iff:
277 // - code model is small OR
278 // - code model is medium and we're emitting externally visible symbols
279 // or any code symbols
280 if (CM == CodeModel::Small ||
281 (CM == CodeModel::Medium && (Global ||
282 Reason != DwarfEncoding::Data)))
283 Format = DW_EH_PE_sdata4;
285 Format = DW_EH_PE_sdata8;
289 Format |= DW_EH_PE_indirect;
291 return (Format | DW_EH_PE_pcrel);
294 (CM == CodeModel::Small ||
295 (CM == CodeModel::Medium && Reason != DwarfEncoding::Data)))
296 return DW_EH_PE_udata4;
298 return DW_EH_PE_absptr;
303 X86COFFTargetAsmInfo::UniqueSectionForGlobal(const GlobalValue* GV,
304 SectionKind::Kind kind) const {
306 case SectionKind::Text:
307 return ".text$linkonce" + GV->getName();
308 case SectionKind::Data:
309 case SectionKind::BSS:
310 case SectionKind::ThreadData:
311 case SectionKind::ThreadBSS:
312 return ".data$linkonce" + GV->getName();
313 case SectionKind::ROData:
314 case SectionKind::RODataMergeConst:
315 case SectionKind::RODataMergeStr:
316 return ".rdata$linkonce" + GV->getName();
318 assert(0 && "Unknown section kind");
323 std::string X86COFFTargetAsmInfo::printSectionFlags(unsigned flags) const {
324 std::string Flags = ",\"";
326 if (flags & SectionFlags::Code)
328 if (flags & SectionFlags::Writeable)
336 X86WinTargetAsmInfo::X86WinTargetAsmInfo(const X86TargetMachine &TM):
337 X86GenericTargetAsmInfo(TM) {
341 PrivateGlobalPrefix = "$";
342 AlignDirective = "\talign\t";
343 ZeroDirective = "\tdb\t";
344 ZeroDirectiveSuffix = " dup(0)";
345 AsciiDirective = "\tdb\t";
347 Data8bitsDirective = "\tdb\t";
348 Data16bitsDirective = "\tdw\t";
349 Data32bitsDirective = "\tdd\t";
350 Data64bitsDirective = "\tdq\t";
351 HasDotTypeDotSizeDirective = false;
352 HasSingleParameterDotFile = false;
354 TextSection = getUnnamedSection("_text", SectionFlags::Code);
355 DataSection = getUnnamedSection("_data", SectionFlags::Writeable);
357 JumpTableDataSection = NULL;
358 SwitchToSectionDirective = "";
359 TextSectionStartSuffix = "\tsegment 'CODE'";
360 DataSectionStartSuffix = "\tsegment 'DATA'";
361 SectionEndDirectiveSuffix = "\tends\n";
364 template <class BaseTAI>
365 bool X86TargetAsmInfo<BaseTAI>::LowerToBSwap(CallInst *CI) const {
366 // FIXME: this should verify that we are targetting a 486 or better. If not,
367 // we will turn this bswap into something that will be lowered to logical ops
368 // instead of emitting the bswap asm. For now, we don't support 486 or lower
369 // so don't worry about this.
371 // Verify this is a simple bswap.
372 if (CI->getNumOperands() != 2 ||
373 CI->getType() != CI->getOperand(1)->getType() ||
374 !CI->getType()->isInteger())
377 const IntegerType *Ty = dyn_cast<IntegerType>(CI->getType());
378 if (!Ty || Ty->getBitWidth() % 16 != 0)
381 // Okay, we can do this xform, do so now.
382 const Type *Tys[] = { Ty };
383 Module *M = CI->getParent()->getParent()->getParent();
384 Constant *Int = Intrinsic::getDeclaration(M, Intrinsic::bswap, Tys, 1);
386 Value *Op = CI->getOperand(1);
387 Op = CallInst::Create(Int, Op, CI->getName(), CI);
389 CI->replaceAllUsesWith(Op);
390 CI->eraseFromParent();
394 template <class BaseTAI>
395 bool X86TargetAsmInfo<BaseTAI>::ExpandInlineAsm(CallInst *CI) const {
396 InlineAsm *IA = cast<InlineAsm>(CI->getCalledValue());
397 std::vector<InlineAsm::ConstraintInfo> Constraints = IA->ParseConstraints();
399 std::string AsmStr = IA->getAsmString();
401 // TODO: should remove alternatives from the asmstring: "foo {a|b}" -> "foo a"
402 std::vector<std::string> AsmPieces;
403 SplitString(AsmStr, AsmPieces, "\n"); // ; as separator?
405 switch (AsmPieces.size()) {
406 default: return false;
408 AsmStr = AsmPieces[0];
410 SplitString(AsmStr, AsmPieces, " \t"); // Split with whitespace.
413 if (AsmPieces.size() == 2 &&
414 (AsmPieces[0] == "bswap" ||
415 AsmPieces[0] == "bswapq" ||
416 AsmPieces[0] == "bswapl") &&
417 (AsmPieces[1] == "$0" ||
418 AsmPieces[1] == "${0:q}")) {
419 // No need to check constraints, nothing other than the equivalent of
420 // "=r,0" would be valid here.
421 return LowerToBSwap(CI);
423 // rorw $$8, ${0:w} --> llvm.bswap.i16
424 if (CI->getType() == Type::Int16Ty &&
425 AsmPieces.size() == 3 &&
426 AsmPieces[0] == "rorw" &&
427 AsmPieces[1] == "$$8," &&
428 AsmPieces[2] == "${0:w}" &&
429 IA->getConstraintString() == "=r,0,~{dirflag},~{fpsr},~{flags},~{cc}") {
430 return LowerToBSwap(CI);
434 if (CI->getType() == Type::Int64Ty && Constraints.size() >= 2 &&
435 Constraints[0].Codes.size() == 1 && Constraints[0].Codes[0] == "A" &&
436 Constraints[1].Codes.size() == 1 && Constraints[1].Codes[0] == "0") {
437 // bswap %eax / bswap %edx / xchgl %eax, %edx -> llvm.bswap.i64
438 std::vector<std::string> Words;
439 SplitString(AsmPieces[0], Words, " \t");
440 if (Words.size() == 2 && Words[0] == "bswap" && Words[1] == "%eax") {
442 SplitString(AsmPieces[1], Words, " \t");
443 if (Words.size() == 2 && Words[0] == "bswap" && Words[1] == "%edx") {
445 SplitString(AsmPieces[2], Words, " \t,");
446 if (Words.size() == 3 && Words[0] == "xchgl" && Words[1] == "%eax" &&
447 Words[2] == "%edx") {
448 return LowerToBSwap(CI);
458 // Instantiate default implementation.
459 TEMPLATE_INSTANTIATION(class X86TargetAsmInfo<TargetAsmInfo>);