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 if (TM.getRelocationModel() == Reloc::Static) {
74 StaticCtorsSection = ".constructor";
75 StaticDtorsSection = ".destructor";
77 StaticCtorsSection = ".mod_init_func";
78 StaticDtorsSection = ".mod_term_func";
81 PersonalityPrefix = "";
82 PersonalitySuffix = "+4@GOTPCREL";
84 PersonalityPrefix = "L";
85 PersonalitySuffix = "$non_lazy_ptr";
87 NeedsIndirectEncoding = true;
88 InlineAsmStart = "## InlineAsm Start";
89 InlineAsmEnd = "## InlineAsm End";
91 SetDirective = "\t.set";
93 UsedDirective = "\t.no_dead_strip\t";
94 WeakDefDirective = "\t.weak_definition ";
95 WeakRefDirective = "\t.weak_reference ";
96 HiddenDirective = "\t.private_extern ";
97 ProtectedDirective = "\t.globl\t";
99 // In non-PIC modes, emit a special label before jump tables so that the
100 // linker can perform more accurate dead code stripping.
101 if (TM.getRelocationModel() != Reloc::PIC_) {
102 // Emit a local label that is preserved until the linker runs.
103 JumpTableSpecialLabelPrefix = "l";
106 SupportsDebugInformation = true;
108 DwarfAbbrevSection = ".section __DWARF,__debug_abbrev,regular,debug";
109 DwarfInfoSection = ".section __DWARF,__debug_info,regular,debug";
110 DwarfLineSection = ".section __DWARF,__debug_line,regular,debug";
111 DwarfFrameSection = ".section __DWARF,__debug_frame,regular,debug";
112 DwarfPubNamesSection = ".section __DWARF,__debug_pubnames,regular,debug";
113 DwarfPubTypesSection = ".section __DWARF,__debug_pubtypes,regular,debug";
114 DwarfStrSection = ".section __DWARF,__debug_str,regular,debug";
115 DwarfLocSection = ".section __DWARF,__debug_loc,regular,debug";
116 DwarfARangesSection = ".section __DWARF,__debug_aranges,regular,debug";
117 DwarfRangesSection = ".section __DWARF,__debug_ranges,regular,debug";
118 DwarfMacInfoSection = ".section __DWARF,__debug_macinfo,regular,debug";
120 // Exceptions handling
121 SupportsExceptionHandling = true;
122 GlobalEHDirective = "\t.globl\t";
123 SupportsWeakOmittedEHFrame = false;
124 AbsoluteEHSectionOffsets = false;
125 DwarfEHFrameSection =
126 ".section __TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support";
127 DwarfExceptionSection = ".section __DATA,__gcc_except_tab";
131 X86DarwinTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
133 if (Reason == DwarfEncoding::Functions && Global)
134 return (DW_EH_PE_pcrel | DW_EH_PE_indirect | DW_EH_PE_sdata4);
135 else if (Reason == DwarfEncoding::CodeLabels || !Global)
136 return DW_EH_PE_pcrel;
138 return DW_EH_PE_absptr;
142 X86DarwinTargetAsmInfo::getEHGlobalPrefix() const
144 const X86Subtarget* Subtarget = &TM.getSubtarget<X86Subtarget>();
145 if (Subtarget->getDarwinVers() > 9)
146 return PrivateGlobalPrefix;
151 X86ELFTargetAsmInfo::X86ELFTargetAsmInfo(const X86TargetMachine &TM):
152 X86TargetAsmInfo<ELFTargetAsmInfo>(TM) {
154 CStringSection = ".rodata.str";
155 PrivateGlobalPrefix = ".L";
156 WeakRefDirective = "\t.weak\t";
157 SetDirective = "\t.set\t";
160 // Set up DWARF directives
161 HasLEB128 = true; // Target asm supports leb128 directives (little-endian)
164 AbsoluteDebugSectionOffsets = true;
165 SupportsDebugInformation = true;
166 DwarfAbbrevSection = "\t.section\t.debug_abbrev,\"\",@progbits";
167 DwarfInfoSection = "\t.section\t.debug_info,\"\",@progbits";
168 DwarfLineSection = "\t.section\t.debug_line,\"\",@progbits";
169 DwarfFrameSection = "\t.section\t.debug_frame,\"\",@progbits";
170 DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"\",@progbits";
171 DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"\",@progbits";
172 DwarfStrSection = "\t.section\t.debug_str,\"\",@progbits";
173 DwarfLocSection = "\t.section\t.debug_loc,\"\",@progbits";
174 DwarfARangesSection = "\t.section\t.debug_aranges,\"\",@progbits";
175 DwarfRangesSection = "\t.section\t.debug_ranges,\"\",@progbits";
176 DwarfMacInfoSection = "\t.section\t.debug_macinfo,\"\",@progbits";
178 // Exceptions handling
179 SupportsExceptionHandling = true;
180 AbsoluteEHSectionOffsets = false;
181 DwarfEHFrameSection = "\t.section\t.eh_frame,\"aw\",@progbits";
182 DwarfExceptionSection = "\t.section\t.gcc_except_table,\"a\",@progbits";
184 // On Linux we must declare when we can use a non-executable stack.
185 if (TM.getSubtarget<X86Subtarget>().isLinux())
186 NonexecutableStackDirective = "\t.section\t.note.GNU-stack,\"\",@progbits";
190 X86ELFTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
192 CodeModel::Model CM = TM.getCodeModel();
193 bool is64Bit = TM.getSubtarget<X86Subtarget>().is64Bit();
195 if (TM.getRelocationModel() == Reloc::PIC_) {
199 // 32 bit targets always encode pointers as 4 bytes
200 Format = DW_EH_PE_sdata4;
202 // 64 bit targets encode pointers in 4 bytes iff:
203 // - code model is small OR
204 // - code model is medium and we're emitting externally visible symbols
205 // or any code symbols
206 if (CM == CodeModel::Small ||
207 (CM == CodeModel::Medium && (Global ||
208 Reason != DwarfEncoding::Data)))
209 Format = DW_EH_PE_sdata4;
211 Format = DW_EH_PE_sdata8;
215 Format |= DW_EH_PE_indirect;
217 return (Format | DW_EH_PE_pcrel);
220 (CM == CodeModel::Small ||
221 (CM == CodeModel::Medium && Reason != DwarfEncoding::Data)))
222 return DW_EH_PE_udata4;
224 return DW_EH_PE_absptr;
228 X86COFFTargetAsmInfo::X86COFFTargetAsmInfo(const X86TargetMachine &TM):
229 X86GenericTargetAsmInfo(TM) {
232 LCOMMDirective = "\t.lcomm\t";
233 COMMDirectiveTakesAlignment = false;
234 HasDotTypeDotSizeDirective = false;
235 HasSingleParameterDotFile = false;
236 StaticCtorsSection = "\t.section .ctors,\"aw\"";
237 StaticDtorsSection = "\t.section .dtors,\"aw\"";
238 HiddenDirective = NULL;
239 PrivateGlobalPrefix = "L"; // Prefix for private global symbols
240 WeakRefDirective = "\t.weak\t";
241 SetDirective = "\t.set\t";
243 // Set up DWARF directives
244 HasLEB128 = true; // Target asm supports leb128 directives (little-endian)
245 AbsoluteDebugSectionOffsets = true;
246 AbsoluteEHSectionOffsets = false;
247 SupportsDebugInformation = true;
248 DwarfSectionOffsetDirective = "\t.secrel32\t";
249 DwarfAbbrevSection = "\t.section\t.debug_abbrev,\"dr\"";
250 DwarfInfoSection = "\t.section\t.debug_info,\"dr\"";
251 DwarfLineSection = "\t.section\t.debug_line,\"dr\"";
252 DwarfFrameSection = "\t.section\t.debug_frame,\"dr\"";
253 DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"dr\"";
254 DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"dr\"";
255 DwarfStrSection = "\t.section\t.debug_str,\"dr\"";
256 DwarfLocSection = "\t.section\t.debug_loc,\"dr\"";
257 DwarfARangesSection = "\t.section\t.debug_aranges,\"dr\"";
258 DwarfRangesSection = "\t.section\t.debug_ranges,\"dr\"";
259 DwarfMacInfoSection = "\t.section\t.debug_macinfo,\"dr\"";
263 X86COFFTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
265 CodeModel::Model CM = TM.getCodeModel();
266 bool is64Bit = TM.getSubtarget<X86Subtarget>().is64Bit();
268 if (TM.getRelocationModel() == Reloc::PIC_) {
272 // 32 bit targets always encode pointers as 4 bytes
273 Format = DW_EH_PE_sdata4;
275 // 64 bit targets encode pointers in 4 bytes iff:
276 // - code model is small OR
277 // - code model is medium and we're emitting externally visible symbols
278 // or any code symbols
279 if (CM == CodeModel::Small ||
280 (CM == CodeModel::Medium && (Global ||
281 Reason != DwarfEncoding::Data)))
282 Format = DW_EH_PE_sdata4;
284 Format = DW_EH_PE_sdata8;
288 Format |= DW_EH_PE_indirect;
290 return (Format | DW_EH_PE_pcrel);
293 (CM == CodeModel::Small ||
294 (CM == CodeModel::Medium && Reason != DwarfEncoding::Data)))
295 return DW_EH_PE_udata4;
297 return DW_EH_PE_absptr;
302 X86COFFTargetAsmInfo::UniqueSectionForGlobal(const GlobalValue* GV,
303 SectionKind::Kind kind) const {
305 case SectionKind::Text:
306 return ".text$linkonce" + GV->getName();
307 case SectionKind::Data:
308 case SectionKind::BSS:
309 case SectionKind::ThreadData:
310 case SectionKind::ThreadBSS:
311 return ".data$linkonce" + GV->getName();
312 case SectionKind::ROData:
313 case SectionKind::RODataMergeConst:
314 case SectionKind::RODataMergeStr:
315 return ".rdata$linkonce" + GV->getName();
317 assert(0 && "Unknown section kind");
321 std::string X86COFFTargetAsmInfo::printSectionFlags(unsigned flags) const {
322 std::string Flags = ",\"";
324 if (flags & SectionFlags::Code)
326 if (flags & SectionFlags::Writeable)
334 X86WinTargetAsmInfo::X86WinTargetAsmInfo(const X86TargetMachine &TM):
335 X86GenericTargetAsmInfo(TM) {
339 PrivateGlobalPrefix = "$";
340 AlignDirective = "\talign\t";
341 ZeroDirective = "\tdb\t";
342 ZeroDirectiveSuffix = " dup(0)";
343 AsciiDirective = "\tdb\t";
345 Data8bitsDirective = "\tdb\t";
346 Data16bitsDirective = "\tdw\t";
347 Data32bitsDirective = "\tdd\t";
348 Data64bitsDirective = "\tdq\t";
349 HasDotTypeDotSizeDirective = false;
350 HasSingleParameterDotFile = false;
352 TextSection = getUnnamedSection("_text", SectionFlags::Code);
353 DataSection = getUnnamedSection("_data", SectionFlags::Writeable);
355 JumpTableDataSection = NULL;
356 SwitchToSectionDirective = "";
357 TextSectionStartSuffix = "\tsegment 'CODE'";
358 DataSectionStartSuffix = "\tsegment 'DATA'";
359 SectionEndDirectiveSuffix = "\tends\n";
362 template <class BaseTAI>
363 bool X86TargetAsmInfo<BaseTAI>::LowerToBSwap(CallInst *CI) const {
364 // FIXME: this should verify that we are targetting a 486 or better. If not,
365 // we will turn this bswap into something that will be lowered to logical ops
366 // instead of emitting the bswap asm. For now, we don't support 486 or lower
367 // so don't worry about this.
369 // Verify this is a simple bswap.
370 if (CI->getNumOperands() != 2 ||
371 CI->getType() != CI->getOperand(1)->getType() ||
372 !CI->getType()->isInteger())
375 const IntegerType *Ty = dyn_cast<IntegerType>(CI->getType());
376 if (!Ty || Ty->getBitWidth() % 16 != 0)
379 // Okay, we can do this xform, do so now.
380 const Type *Tys[] = { Ty };
381 Module *M = CI->getParent()->getParent()->getParent();
382 Constant *Int = Intrinsic::getDeclaration(M, Intrinsic::bswap, Tys, 1);
384 Value *Op = CI->getOperand(1);
385 Op = CallInst::Create(Int, Op, CI->getName(), CI);
387 CI->replaceAllUsesWith(Op);
388 CI->eraseFromParent();
392 template <class BaseTAI>
393 bool X86TargetAsmInfo<BaseTAI>::ExpandInlineAsm(CallInst *CI) const {
394 InlineAsm *IA = cast<InlineAsm>(CI->getCalledValue());
395 std::vector<InlineAsm::ConstraintInfo> Constraints = IA->ParseConstraints();
397 std::string AsmStr = IA->getAsmString();
399 // TODO: should remove alternatives from the asmstring: "foo {a|b}" -> "foo a"
400 std::vector<std::string> AsmPieces;
401 SplitString(AsmStr, AsmPieces, "\n"); // ; as separator?
403 switch (AsmPieces.size()) {
404 default: return false;
406 AsmStr = AsmPieces[0];
408 SplitString(AsmStr, AsmPieces, " \t"); // Split with whitespace.
411 if (AsmPieces.size() == 2 &&
412 AsmPieces[0] == "bswap" && AsmPieces[1] == "$0") {
413 // No need to check constraints, nothing other than the equivalent of
414 // "=r,0" would be valid here.
415 return LowerToBSwap(CI);
419 if (CI->getType() == Type::Int64Ty && Constraints.size() >= 2 &&
420 Constraints[0].Codes.size() == 1 && Constraints[0].Codes[0] == "A" &&
421 Constraints[1].Codes.size() == 1 && Constraints[1].Codes[0] == "0") {
422 // bswap %eax / bswap %edx / xchgl %eax, %edx -> llvm.bswap.i64
423 std::vector<std::string> Words;
424 SplitString(AsmPieces[0], Words, " \t");
425 if (Words.size() == 2 && Words[0] == "bswap" && Words[1] == "%eax") {
427 SplitString(AsmPieces[1], Words, " \t");
428 if (Words.size() == 2 && Words[0] == "bswap" && Words[1] == "%edx") {
430 SplitString(AsmPieces[2], Words, " \t,");
431 if (Words.size() == 3 && Words[0] == "xchgl" && Words[1] == "%eax" &&
432 Words[2] == "%edx") {
433 return LowerToBSwap(CI);
443 // Instantiate default implementation.
444 TEMPLATE_INSTANTIATION(class X86TargetAsmInfo<TargetAsmInfo>);