// Emit the rest of the function body.
EmitFunctionBody();
+ // If we need V4T thumb mode Register Indirect Jump pads, emit them.
+ // These are created per function, rather than per TU, since it's
+ // relatively easy to exceed the thumb branch range within a TU.
+ if (! ThumbIndirectPads.empty()) {
+ OutStreamer.EmitAssemblerFlag(MCAF_Code16);
+ EmitAlignment(1);
+ for (unsigned i = 0, e = ThumbIndirectPads.size(); i < e; i++) {
+ OutStreamer.EmitLabel(ThumbIndirectPads[i].second);
+ EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tBX)
+ .addReg(ThumbIndirectPads[i].first)
+ // Add predicate operands.
+ .addImm(ARMCC::AL)
+ .addReg(0));
+ }
+ ThumbIndirectPads.clear();
+ }
+
// We didn't modify anything.
return false;
}
// Signal various FP modes.
if (!TM.Options.UnsafeFPMath) {
- ATS.emitAttribute(ARMBuildAttrs::ABI_FP_denormal, ARMBuildAttrs::Allowed);
+ ATS.emitAttribute(ARMBuildAttrs::ABI_FP_denormal,
+ ARMBuildAttrs::IEEEDenormals);
ATS.emitAttribute(ARMBuildAttrs::ABI_FP_exceptions,
ARMBuildAttrs::Allowed);
+
+ // If the user has permitted this code to choose the IEEE 754
+ // rounding at run-time, emit the rounding attribute.
+ if (TM.Options.HonorSignDependentRoundingFPMathOption)
+ ATS.emitAttribute(ARMBuildAttrs::ABI_FP_rounding,
+ ARMBuildAttrs::Allowed);
+ } else {
+ if (!Subtarget->hasVFP2()) {
+ // When the target doesn't have an FPU (by design or
+ // intention), the assumptions made on the software support
+ // mirror that of the equivalent hardware support *if it
+ // existed*. For v7 and better we indicate that denormals are
+ // flushed preserving sign, and for V6 we indicate that
+ // denormals are flushed to positive zero.
+ if (Subtarget->hasV7Ops())
+ ATS.emitAttribute(ARMBuildAttrs::ABI_FP_denormal,
+ ARMBuildAttrs::PreserveFPSign);
+ } else if (Subtarget->hasVFP3()) {
+ // In VFPv4, VFPv4U, VFPv3, or VFPv3U, it is preserved. That is,
+ // the sign bit of the zero matches the sign bit of the input or
+ // result that is being flushed to zero.
+ ATS.emitAttribute(ARMBuildAttrs::ABI_FP_denormal,
+ ARMBuildAttrs::PreserveFPSign);
+ }
+ // For VFPv2 implementations it is implementation defined as
+ // to whether denormals are flushed to positive zero or to
+ // whatever the sign of zero is (ARM v7AR ARM 2.7.5). Historically
+ // LLVM has chosen to flush this to positive zero (most likely for
+ // GCC compatibility), so that's the chosen value here (the
+ // absence of its emission implies zero).
}
+ // TM.Options.NoInfsFPMath && TM.Options.NoNaNsFPMath is the
+ // equivalent of GCC's -ffinite-math-only flag.
if (TM.Options.NoInfsFPMath && TM.Options.NoNaNsFPMath)
ATS.emitAttribute(ARMBuildAttrs::ABI_FP_number_model,
ARMBuildAttrs::Allowed);
if (Subtarget->hasFP16())
ATS.emitAttribute(ARMBuildAttrs::FP_HP_extension, ARMBuildAttrs::AllowHPFP);
+ // FIXME: To support emitting this build attribute as GCC does, the
+ // -mfp16-format option and associated plumbing must be
+ // supported. For now the __fp16 type is exposed by default, so this
+ // attribute should be emitted with value 1.
+ ATS.emitAttribute(ARMBuildAttrs::ABI_FP_16bit_format,
+ ARMBuildAttrs::FP16FormatIEEE);
+
if (Subtarget->hasMPExtension())
ATS.emitAttribute(ARMBuildAttrs::MPextension_use, ARMBuildAttrs::AllowMP);
if (const Module *SourceModule = MMI->getModule()) {
// ABI_PCS_wchar_t to indicate wchar_t width
// FIXME: There is no way to emit value 0 (wchar_t prohibited).
- if (auto WCharWidthValue = cast_or_null<ConstantInt>(
+ if (auto WCharWidthValue = mdconst::extract_or_null<ConstantInt>(
SourceModule->getModuleFlag("wchar_size"))) {
int WCharWidth = WCharWidthValue->getZExtValue();
assert((WCharWidth == 2 || WCharWidth == 4) &&
// ABI_enum_size to indicate enum width
// FIXME: There is no way to emit value 0 (enums prohibited) or value 3
// (all enums contain a value needing 32 bits to encode).
- if (auto EnumWidthValue = cast_or_null<ConstantInt>(
+ if (auto EnumWidthValue = mdconst::extract_or_null<ConstantInt>(
SourceModule->getModuleFlag("min_enum_size"))) {
int EnumWidth = EnumWidthValue->getZExtValue();
assert((EnumWidth == 1 || EnumWidth == 4) &&
return;
}
case ARM::tBX_CALL: {
- EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tMOVr)
- .addReg(ARM::LR)
- .addReg(ARM::PC)
- // Add predicate operands.
- .addImm(ARMCC::AL)
- .addReg(0));
+ if (Subtarget->hasV5TOps())
+ llvm_unreachable("Expected BLX to be selected for v5t+");
+
+ // On ARM v4t, when doing a call from thumb mode, we need to ensure
+ // that the saved lr has its LSB set correctly (the arch doesn't
+ // have blx).
+ // So here we generate a bl to a small jump pad that does bx rN.
+ // The jump pads are emitted after the function body.
+
+ unsigned TReg = MI->getOperand(0).getReg();
+ MCSymbol *TRegSym = nullptr;
+ for (unsigned i = 0, e = ThumbIndirectPads.size(); i < e; i++) {
+ if (ThumbIndirectPads[i].first == TReg) {
+ TRegSym = ThumbIndirectPads[i].second;
+ break;
+ }
+ }
- EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tBX)
- .addReg(MI->getOperand(0).getReg())
- // Add predicate operands.
- .addImm(ARMCC::AL)
- .addReg(0));
+ if (!TRegSym) {
+ TRegSym = OutContext.CreateTempSymbol();
+ ThumbIndirectPads.push_back(std::make_pair(TReg, TRegSym));
+ }
+
+ // Create a link-saving branch to the Reg Indirect Jump Pad.
+ EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tBL)
+ // Predicate comes first here.
+ .addImm(ARMCC::AL).addReg(0)
+ .addExpr(MCSymbolRefExpr::Create(TRegSym, OutContext)));
return;
}
case ARM::BMOVPCRX_CALL: {