1 //===-- MipsSubtarget.cpp - Mips Subtarget Information --------------------===//
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 implements the Mips specific subclass of TargetSubtargetInfo.
12 //===----------------------------------------------------------------------===//
14 #include "MipsMachineFunction.h"
16 #include "MipsRegisterInfo.h"
17 #include "MipsSubtarget.h"
18 #include "MipsTargetMachine.h"
19 #include "llvm/IR/Attributes.h"
20 #include "llvm/IR/Function.h"
21 #include "llvm/Support/CommandLine.h"
22 #include "llvm/Support/Debug.h"
23 #include "llvm/Support/TargetRegistry.h"
24 #include "llvm/Support/raw_ostream.h"
28 #define DEBUG_TYPE "mips-subtarget"
30 #define GET_SUBTARGETINFO_TARGET_DESC
31 #define GET_SUBTARGETINFO_CTOR
32 #include "MipsGenSubtargetInfo.inc"
34 // FIXME: Maybe this should be on by default when Mips16 is specified
36 static cl::opt<bool> Mixed16_32(
39 cl::desc("Allow for a mixture of Mips16 "
40 "and Mips32 code in a single source file"),
43 static cl::opt<bool> Mips_Os16(
46 cl::desc("Compile all functions that don' use "
47 "floating point as Mips 16"),
51 Mips16HardFloat("mips16-hard-float", cl::NotHidden,
52 cl::desc("MIPS: mips16 hard float enable."),
56 Mips16ConstantIslands(
57 "mips16-constant-islands", cl::NotHidden,
58 cl::desc("MIPS: mips16 constant islands enable."),
61 /// Select the Mips CPU for the given triple and cpu name.
62 /// FIXME: Merge with the copy in MipsMCTargetDesc.cpp
63 static inline StringRef selectMipsCPU(StringRef TT, StringRef CPU) {
64 if (CPU.empty() || CPU == "generic") {
66 if (TheTriple.getArch() == Triple::mips ||
67 TheTriple.getArch() == Triple::mipsel)
75 void MipsSubtarget::anchor() { }
77 MipsSubtarget::MipsSubtarget(const std::string &TT, const std::string &CPU,
78 const std::string &FS, bool little,
79 Reloc::Model _RM, MipsTargetMachine *_TM)
80 : MipsGenSubtargetInfo(TT, CPU, FS), MipsArchVersion(Mips32),
81 MipsABI(UnknownABI), IsLittle(little), IsSingleFloat(false),
82 IsFP64bit(false), IsNaN2008bit(false), IsGP64bit(false), HasVFPU(false),
83 HasCnMips(false), IsLinux(true), HasSEInReg(false), HasCondMov(false),
84 HasSwap(false), HasBitCount(false), HasFPIdx(false), InMips16Mode(false),
85 InMips16HardFloat(Mips16HardFloat), InMicroMipsMode(false), HasDSP(false),
86 HasDSPR2(false), AllowMixed16_32(Mixed16_32 | Mips_Os16), Os16(Mips_Os16),
87 HasMSA(false), RM(_RM), OverrideMode(NoOverride), TM(_TM),
89 std::string CPUName = CPU;
90 CPUName = selectMipsCPU(TT, CPUName);
92 // Parse features string.
93 ParseSubtargetFeatures(CPUName, FS);
95 if (InMips16Mode && !TM->Options.UseSoftFloat) {
96 // Hard float for mips16 means essentially to compile as soft float
97 // but to use a runtime library for soft float that is written with
98 // native mips32 floating point instructions (those runtime routines
99 // run in mips32 hard float mode).
100 TM->Options.UseSoftFloat = true;
101 TM->Options.FloatABIType = FloatABI::Soft;
102 InMips16HardFloat = true;
105 PreviousInMips16Mode = InMips16Mode;
107 // Initialize scheduling itinerary for the specified CPU.
108 InstrItins = getInstrItineraryForCPU(CPUName);
110 // Don't even attempt to generate code for MIPS-I, MIPS-II, MIPS-III, and
111 // MIPS-V. They have not been tested and currently exist for the integrated
113 if (MipsArchVersion == Mips1)
114 report_fatal_error("Code generation for MIPS-I is not implemented", false);
115 if (MipsArchVersion == Mips2)
116 report_fatal_error("Code generation for MIPS-II is not implemented", false);
117 if (MipsArchVersion == Mips3)
118 report_fatal_error("Code generation for MIPS-III is not implemented",
120 if (MipsArchVersion == Mips5)
121 report_fatal_error("Code generation for MIPS-V is not implemented", false);
123 // Assert exactly one ABI was chosen.
124 assert(MipsABI != UnknownABI);
125 assert((((getFeatureBits() & Mips::FeatureO32) != 0) +
126 ((getFeatureBits() & Mips::FeatureEABI) != 0) +
127 ((getFeatureBits() & Mips::FeatureN32) != 0) +
128 ((getFeatureBits() & Mips::FeatureN64) != 0)) == 1);
130 // Check if Architecture and ABI are compatible.
131 assert(((!isGP64bit() && (isABI_O32() || isABI_EABI())) ||
132 (isGP64bit() && (isABI_N32() || isABI_N64()))) &&
133 "Invalid Arch & ABI pair.");
135 if (hasMSA() && !isFP64bit())
136 report_fatal_error("MSA requires a 64-bit FPU register file (FR=1 mode). "
141 StringRef ISA = hasMips64r6() ? "MIPS64r6" : "MIPS32r6";
146 report_fatal_error(ISA + " is not compatible with the DSP ASE", false);
149 // Is the target system Linux ?
150 if (TT.find("linux") == std::string::npos)
153 // Set UseSmallSection.
154 // TODO: Investigate the IsLinux check. I suspect it's really checking for
156 UseSmallSection = !IsLinux && (RM == Reloc::Static);
157 // set some subtarget specific features
163 MipsSubtarget::enablePostRAScheduler(CodeGenOpt::Level OptLevel,
164 TargetSubtargetInfo::AntiDepBreakMode &Mode,
165 RegClassVector &CriticalPathRCs) const {
166 Mode = TargetSubtargetInfo::ANTIDEP_NONE;
167 CriticalPathRCs.clear();
168 CriticalPathRCs.push_back(isGP64bit() ? &Mips::GPR64RegClass
169 : &Mips::GPR32RegClass);
170 return OptLevel >= CodeGenOpt::Aggressive;
173 //FIXME: This logic for reseting the subtarget along with
174 // the helper classes can probably be simplified but there are a lot of
175 // cases so we will defer rewriting this to later.
177 void MipsSubtarget::resetSubtarget(MachineFunction *MF) {
178 bool ChangeToMips16 = false, ChangeToNoMips16 = false;
179 DEBUG(dbgs() << "resetSubtargetFeatures" << "\n");
180 AttributeSet FnAttrs = MF->getFunction()->getAttributes();
181 ChangeToMips16 = FnAttrs.hasAttribute(AttributeSet::FunctionIndex,
183 ChangeToNoMips16 = FnAttrs.hasAttribute(AttributeSet::FunctionIndex,
185 assert (!(ChangeToMips16 & ChangeToNoMips16) &&
186 "mips16 and nomips16 specified on the same function");
187 if (ChangeToMips16) {
188 if (PreviousInMips16Mode)
190 OverrideMode = Mips16Override;
191 PreviousInMips16Mode = true;
192 TM->setHelperClassesMips16();
194 } else if (ChangeToNoMips16) {
195 if (!PreviousInMips16Mode)
197 OverrideMode = NoMips16Override;
198 PreviousInMips16Mode = false;
199 TM->setHelperClassesMipsSE();
202 if (OverrideMode == NoOverride)
204 OverrideMode = NoOverride;
205 DEBUG(dbgs() << "back to default" << "\n");
206 if (inMips16Mode() && !PreviousInMips16Mode) {
207 TM->setHelperClassesMips16();
208 PreviousInMips16Mode = true;
209 } else if (!inMips16Mode() && PreviousInMips16Mode) {
210 TM->setHelperClassesMipsSE();
211 PreviousInMips16Mode = false;
217 bool MipsSubtarget::mipsSEUsesSoftFloat() const {
218 return TM->Options.UseSoftFloat && !InMips16HardFloat;
221 bool MipsSubtarget::useConstantIslands() {
222 DEBUG(dbgs() << "use constant islands " << Mips16ConstantIslands << "\n");
223 return Mips16ConstantIslands;