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"
25 static const char* x86_asm_table[] = {"{si}", "S",
36 X86TargetAsmInfo::X86TargetAsmInfo(const X86TargetMachine &TM) {
37 const X86Subtarget *Subtarget = &TM.getSubtarget<X86Subtarget>();
39 // FIXME - Should be simplified.
41 AsmTransCBE = x86_asm_table;
43 switch (Subtarget->TargetType) {
44 case X86Subtarget::isDarwin:
45 AlignmentIsInBytes = false;
47 if (!Subtarget->is64Bit())
48 Data64bitsDirective = 0; // we can't emit a 64-bit unit
49 ZeroDirective = "\t.space\t"; // ".space N" emits N zeros.
50 PrivateGlobalPrefix = "L"; // Marker for constant pool idxs
51 BSSSection = 0; // no BSS section.
52 ZeroFillDirective = "\t.zerofill\t"; // Uses .zerofill
53 ConstantPoolSection = "\t.const\n";
54 JumpTableDataSection = "\t.const\n";
55 CStringSection = "\t.cstring";
56 FourByteConstantSection = "\t.literal4\n";
57 EightByteConstantSection = "\t.literal8\n";
58 if (Subtarget->is64Bit())
59 SixteenByteConstantSection = "\t.literal16\n";
60 ReadOnlySection = "\t.const\n";
61 LCOMMDirective = "\t.lcomm\t";
62 COMMDirectiveTakesAlignment = false;
63 HasDotTypeDotSizeDirective = false;
64 if (TM.getRelocationModel() == Reloc::Static) {
65 StaticCtorsSection = ".constructor";
66 StaticDtorsSection = ".destructor";
68 StaticCtorsSection = ".mod_init_func";
69 StaticDtorsSection = ".mod_term_func";
71 PersonalityPrefix = "L";
72 PersonalitySuffix = "$non_lazy_ptr";
73 NeedsIndirectEncoding = true;
74 InlineAsmStart = "# InlineAsm Start";
75 InlineAsmEnd = "# InlineAsm End";
76 SetDirective = "\t.set";
78 UsedDirective = "\t.no_dead_strip\t";
79 WeakDefDirective = "\t.weak_definition ";
80 WeakRefDirective = "\t.weak_reference ";
81 HiddenDirective = "\t.private_extern ";
83 // In non-PIC modes, emit a special label before jump tables so that the
84 // linker can perform more accurate dead code stripping.
85 if (TM.getRelocationModel() != Reloc::PIC_) {
86 // Emit a local label that is preserved until the linker runs.
87 JumpTableSpecialLabelPrefix = "l";
90 SupportsDebugInformation = true;
92 DwarfAbbrevSection = ".section __DWARF,__debug_abbrev,regular,debug";
93 DwarfInfoSection = ".section __DWARF,__debug_info,regular,debug";
94 DwarfLineSection = ".section __DWARF,__debug_line,regular,debug";
95 DwarfFrameSection = ".section __DWARF,__debug_frame,regular,debug";
96 DwarfPubNamesSection = ".section __DWARF,__debug_pubnames,regular,debug";
97 DwarfPubTypesSection = ".section __DWARF,__debug_pubtypes,regular,debug";
98 DwarfStrSection = ".section __DWARF,__debug_str,regular,debug";
99 DwarfLocSection = ".section __DWARF,__debug_loc,regular,debug";
100 DwarfARangesSection = ".section __DWARF,__debug_aranges,regular,debug";
101 DwarfRangesSection = ".section __DWARF,__debug_ranges,regular,debug";
102 DwarfMacInfoSection = ".section __DWARF,__debug_macinfo,regular,debug";
104 // Exceptions handling
105 if (!Subtarget->is64Bit())
106 SupportsExceptionHandling = true;
107 GlobalEHDirective = "\t.globl\t";
108 SupportsWeakOmittedEHFrame = false;
109 AbsoluteEHSectionOffsets = false;
110 DwarfEHFrameSection =
111 ".section __TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support";
112 DwarfExceptionSection = ".section __DATA,__gcc_except_tab";
115 case X86Subtarget::isELF:
116 ReadOnlySection = "\t.section\t.rodata";
117 FourByteConstantSection = "\t.section\t.rodata.cst4,\"aM\",@progbits,4";
118 EightByteConstantSection = "\t.section\t.rodata.cst8,\"aM\",@progbits,8";
119 SixteenByteConstantSection = "\t.section\t.rodata.cst16,\"aM\",@progbits,16";
120 CStringSection = "\t.section\t.rodata.str1.1,\"aMS\",@progbits,1";
121 PrivateGlobalPrefix = ".L";
122 WeakRefDirective = "\t.weak\t";
123 SetDirective = "\t.set\t";
126 // Set up DWARF directives
127 HasLEB128 = true; // Target asm supports leb128 directives (little-endian)
130 AbsoluteDebugSectionOffsets = true;
131 SupportsDebugInformation = true;
132 DwarfAbbrevSection = "\t.section\t.debug_abbrev,\"\",@progbits";
133 DwarfInfoSection = "\t.section\t.debug_info,\"\",@progbits";
134 DwarfLineSection = "\t.section\t.debug_line,\"\",@progbits";
135 DwarfFrameSection = "\t.section\t.debug_frame,\"\",@progbits";
136 DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"\",@progbits";
137 DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"\",@progbits";
138 DwarfStrSection = "\t.section\t.debug_str,\"\",@progbits";
139 DwarfLocSection = "\t.section\t.debug_loc,\"\",@progbits";
140 DwarfARangesSection = "\t.section\t.debug_aranges,\"\",@progbits";
141 DwarfRangesSection = "\t.section\t.debug_ranges,\"\",@progbits";
142 DwarfMacInfoSection = "\t.section\t.debug_macinfo,\"\",@progbits";
144 // Exceptions handling
145 if (!Subtarget->is64Bit())
146 SupportsExceptionHandling = true;
147 AbsoluteEHSectionOffsets = false;
148 DwarfEHFrameSection = "\t.section\t.eh_frame,\"aw\",@progbits";
149 DwarfExceptionSection = "\t.section\t.gcc_except_table,\"a\",@progbits";
152 case X86Subtarget::isCygwin:
153 case X86Subtarget::isMingw:
155 LCOMMDirective = "\t.lcomm\t";
156 COMMDirectiveTakesAlignment = false;
157 HasDotTypeDotSizeDirective = false;
158 StaticCtorsSection = "\t.section .ctors,\"aw\"";
159 StaticDtorsSection = "\t.section .dtors,\"aw\"";
160 HiddenDirective = NULL;
161 PrivateGlobalPrefix = "L"; // Prefix for private global symbols
162 WeakRefDirective = "\t.weak\t";
163 SetDirective = "\t.set\t";
165 // Set up DWARF directives
166 HasLEB128 = true; // Target asm supports leb128 directives (little-endian)
167 AbsoluteDebugSectionOffsets = true;
168 AbsoluteEHSectionOffsets = false;
169 SupportsDebugInformation = true;
170 DwarfSectionOffsetDirective = "\t.secrel32\t";
171 DwarfAbbrevSection = "\t.section\t.debug_abbrev,\"dr\"";
172 DwarfInfoSection = "\t.section\t.debug_info,\"dr\"";
173 DwarfLineSection = "\t.section\t.debug_line,\"dr\"";
174 DwarfFrameSection = "\t.section\t.debug_frame,\"dr\"";
175 DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"dr\"";
176 DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"dr\"";
177 DwarfStrSection = "\t.section\t.debug_str,\"dr\"";
178 DwarfLocSection = "\t.section\t.debug_loc,\"dr\"";
179 DwarfARangesSection = "\t.section\t.debug_aranges,\"dr\"";
180 DwarfRangesSection = "\t.section\t.debug_ranges,\"dr\"";
181 DwarfMacInfoSection = "\t.section\t.debug_macinfo,\"dr\"";
184 case X86Subtarget::isWindows:
186 HasDotTypeDotSizeDirective = false;
192 if (Subtarget->isFlavorIntel()) {
196 PrivateGlobalPrefix = "$";
197 AlignDirective = "\talign\t";
198 ZeroDirective = "\tdb\t";
199 ZeroDirectiveSuffix = " dup(0)";
200 AsciiDirective = "\tdb\t";
202 Data8bitsDirective = "\tdb\t";
203 Data16bitsDirective = "\tdw\t";
204 Data32bitsDirective = "\tdd\t";
205 Data64bitsDirective = "\tdq\t";
206 HasDotTypeDotSizeDirective = false;
208 TextSection = "_text";
209 DataSection = "_data";
210 JumpTableDataSection = NULL;
211 SwitchToSectionDirective = "";
212 TextSectionStartSuffix = "\tsegment 'CODE'";
213 DataSectionStartSuffix = "\tsegment 'DATA'";
214 SectionEndDirectiveSuffix = "\tends\n";
217 AssemblerDialect = Subtarget->getAsmFlavor();
220 bool X86TargetAsmInfo::LowerToBSwap(CallInst *CI) const {
221 // FIXME: this should verify that we are targetting a 486 or better. If not,
222 // we will turn this bswap into something that will be lowered to logical ops
223 // instead of emitting the bswap asm. For now, we don't support 486 or lower
224 // so don't worry about this.
226 // Verify this is a simple bswap.
227 if (CI->getNumOperands() != 2 ||
228 CI->getType() != CI->getOperand(1)->getType() ||
229 !CI->getType()->isInteger())
232 const IntegerType *Ty = dyn_cast<IntegerType>(CI->getType());
233 if (!Ty || Ty->getBitWidth() % 16 != 0)
236 // Okay, we can do this xform, do so now.
237 const Type *Tys[] = { Ty };
238 Module *M = CI->getParent()->getParent()->getParent();
239 Constant *Int = Intrinsic::getDeclaration(M, Intrinsic::bswap, Tys, 1);
241 Value *Op = CI->getOperand(1);
242 Op = new CallInst(Int, Op, CI->getName(), CI);
244 CI->replaceAllUsesWith(Op);
245 CI->eraseFromParent();
250 bool X86TargetAsmInfo::ExpandInlineAsm(CallInst *CI) const {
251 InlineAsm *IA = cast<InlineAsm>(CI->getCalledValue());
252 std::vector<InlineAsm::ConstraintInfo> Constraints = IA->ParseConstraints();
254 std::string AsmStr = IA->getAsmString();
256 // TODO: should remove alternatives from the asmstring: "foo {a|b}" -> "foo a"
257 std::vector<std::string> AsmPieces;
258 SplitString(AsmStr, AsmPieces, "\n"); // ; as separator?
260 switch (AsmPieces.size()) {
261 default: return false;
263 AsmStr = AsmPieces[0];
265 SplitString(AsmStr, AsmPieces, " \t"); // Split with whitespace.
268 if (AsmPieces.size() == 2 &&
269 AsmPieces[0] == "bswap" && AsmPieces[1] == "$0") {
270 // No need to check constraints, nothing other than the equivalent of
271 // "=r,0" would be valid here.
272 return LowerToBSwap(CI);
276 if (CI->getType() == Type::Int64Ty && Constraints.size() >= 2 &&
277 Constraints[0].Codes.size() == 1 && Constraints[0].Codes[0] == "A" &&
278 Constraints[1].Codes.size() == 1 && Constraints[1].Codes[0] == "0") {
279 // bswap %eax / bswap %edx / xchgl %eax, %edx -> llvm.bswap.i64
280 std::vector<std::string> Words;
281 SplitString(AsmPieces[0], Words, " \t");
282 if (Words.size() == 2 && Words[0] == "bswap" && Words[1] == "%eax") {
284 SplitString(AsmPieces[1], Words, " \t");
285 if (Words.size() == 2 && Words[0] == "bswap" && Words[1] == "%edx") {
287 SplitString(AsmPieces[2], Words, " \t,");
288 if (Words.size() == 3 && Words[0] == "xchgl" && Words[1] == "%eax" &&
289 Words[2] == "%edx") {
290 return LowerToBSwap(CI);