From 8464fff30b16d39227444985bb7c8cc7fd12d66d Mon Sep 17 00:00:00 2001 From: Akira Hatanaka Date: Tue, 7 Jun 2011 02:17:21 +0000 Subject: [PATCH] Add test case for C++ exception handling and fix the following mistakes in MipsFrameLowering::emitPrologue: - cfi directives are not inserted at the right location or in the right order. - The source MachineLocation for the cfi directive that changes the cfa register to $fp should be MachineLocation::VirtualFP. - A PROLOG_LABEL that marks the beginning of cfi_offset directives for callee-saved register is emitted even when no callee-saved registers are saved. - When a callee-saved double precision register is saved, two cfi_offset directives, one for each of the paired single precision registers, should be emitted. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132703 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/Mips/MipsFrameLowering.cpp | 90 ++++++++++++++++++--------- test/CodeGen/Mips/eh.ll | 78 +++++++++++++++++++++++ 2 files changed, 138 insertions(+), 30 deletions(-) create mode 100644 test/CodeGen/Mips/eh.ll diff --git a/lib/Target/Mips/MipsFrameLowering.cpp b/lib/Target/Mips/MipsFrameLowering.cpp index 091c1b248fb..c1ceda7ab0c 100644 --- a/lib/Target/Mips/MipsFrameLowering.cpp +++ b/lib/Target/Mips/MipsFrameLowering.cpp @@ -173,6 +173,10 @@ void MipsFrameLowering::emitPrologue(MachineFunction &MF) const { // No need to allocate space on the stack. if (StackSize == 0 && !MFI->adjustsStack()) return; + MachineModuleInfo &MMI = MF.getMMI(); + std::vector &Moves = MMI.getFrameMoves(); + MachineLocation DstML, SrcML; + // Adjust stack : addi sp, sp, (-imm) ATUsed = expandRegLargeImmPair(Mips::SP, -StackSize, NewReg, NewImm, MBB, MBBI); @@ -183,49 +187,75 @@ void MipsFrameLowering::emitPrologue(MachineFunction &MF) const { if (ATUsed) BuildMI(MBB, MBBI, dl, TII.get(Mips::ATMACRO)); + // emit ".cfi_def_cfa_offset StackSize" + MCSymbol *AdjustSPLabel = MMI.getContext().CreateTempSymbol(); + BuildMI(MBB, MBBI, dl, + TII.get(TargetOpcode::PROLOG_LABEL)).addSym(AdjustSPLabel); + DstML = MachineLocation(MachineLocation::VirtualFP); + SrcML = MachineLocation(MachineLocation::VirtualFP, -StackSize); + Moves.push_back(MachineMove(AdjustSPLabel, DstML, SrcML)); + // Find the instruction past the last instruction that saves a callee-saved // register to the stack. const std::vector &CSI = MFI->getCalleeSavedInfo(); - - for (unsigned i = 0; i < CSI.size(); ++i) - ++MBBI; + + if (CSI.size()) { + for (unsigned i = 0; i < CSI.size(); ++i) + ++MBBI; + // Iterate over list of callee-saved registers and emit .cfi_offset directives. + MCSymbol *CSLabel = MMI.getContext().CreateTempSymbol(); + BuildMI(MBB, MBBI, dl, + TII.get(TargetOpcode::PROLOG_LABEL)).addSym(CSLabel); + + for (std::vector::const_iterator I = CSI.begin(), + E = CSI.end(); I != E; ++I) { + int64_t Offset = MFI->getObjectOffset(I->getFrameIdx()); + unsigned Reg = I->getReg(); + + // If Reg is a double precision register, emit two cfa_offsets, + // one for each of the paired single precision registers. + if (Mips::AFGR64RegisterClass->contains(Reg)) { + const unsigned *SubRegs = RegInfo->getSubRegisters(Reg); + MachineLocation DstML0(MachineLocation::VirtualFP, Offset); + MachineLocation DstML1(MachineLocation::VirtualFP, Offset + 4); + MachineLocation SrcML0(*SubRegs); + MachineLocation SrcML1(*(SubRegs + 1)); + + if (!STI.isLittle()) + std::swap(SrcML0, SrcML1); + + Moves.push_back(MachineMove(CSLabel, DstML0, SrcML0)); + Moves.push_back(MachineMove(CSLabel, DstML1, SrcML1)); + } + else { + // Reg is either in CPURegs or FGR32. + DstML = MachineLocation(MachineLocation::VirtualFP, Offset); + SrcML = MachineLocation(Reg); + Moves.push_back(MachineMove(CSLabel, DstML, SrcML)); + } + } + } + // if framepointer enabled, set it to point to the stack pointer. - if (hasFP(MF)) + if (hasFP(MF)) { // Insert instruction "move $fp, $sp" at this location. BuildMI(MBB, MBBI, dl, TII.get(Mips::ADDu), Mips::FP) .addReg(Mips::SP).addReg(Mips::ZERO); + // emit ".cfi_def_cfa_register $fp" + MCSymbol *SetFPLabel = MMI.getContext().CreateTempSymbol(); + BuildMI(MBB, MBBI, dl, + TII.get(TargetOpcode::PROLOG_LABEL)).addSym(SetFPLabel); + DstML = MachineLocation(Mips::FP); + SrcML = MachineLocation(MachineLocation::VirtualFP); + Moves.push_back(MachineMove(SetFPLabel, DstML, SrcML)); + } + // Restore GP from the saved stack location if (MipsFI->needGPSaveRestore()) BuildMI(MBB, MBBI, dl, TII.get(Mips::CPRESTORE)) .addImm(MFI->getObjectOffset(MipsFI->getGPFI())); - - // EH Frame infomation. - MachineModuleInfo &MMI = MF.getMMI(); - std::vector &Moves = MMI.getFrameMoves(); - MCSymbol *FrameLabel = MMI.getContext().CreateTempSymbol(); - BuildMI(MBB, MBBI, dl, TII.get(TargetOpcode::PROLOG_LABEL)).addSym(FrameLabel); - - if (hasFP(MF)) { - MachineLocation SPDst(Mips::FP); - MachineLocation SPSrc(Mips::SP); - Moves.push_back(MachineMove(FrameLabel, SPDst, SPSrc)); - } - - if (StackSize) { - MachineLocation SPDst(MachineLocation::VirtualFP); - MachineLocation SPSrc(MachineLocation::VirtualFP, -StackSize); - Moves.push_back(MachineMove(FrameLabel, SPDst, SPSrc)); - } - - for (std::vector::const_iterator I = CSI.begin(), - E = CSI.end(); I != E; ++I) { - int64_t Offset = MFI->getObjectOffset(I->getFrameIdx()); - MachineLocation CSDst(MachineLocation::VirtualFP, Offset); - MachineLocation CSSrc(I->getReg()); - Moves.push_back(MachineMove(FrameLabel, CSDst, CSSrc)); - } } void MipsFrameLowering::emitEpilogue(MachineFunction &MF, diff --git a/test/CodeGen/Mips/eh.ll b/test/CodeGen/Mips/eh.ll new file mode 100644 index 00000000000..765b7783e5d --- /dev/null +++ b/test/CodeGen/Mips/eh.ll @@ -0,0 +1,78 @@ +; RUN: llc < %s -march=mipsel -mcpu=4ke | FileCheck %s -check-prefix=CHECK-EL +; RUN: llc < %s -march=mips -mcpu=4ke | FileCheck %s -check-prefix=CHECK-EB + +@g1 = global double 0.000000e+00, align 8 +@_ZTId = external constant i8* + +define void @_Z1fd(double %i2) { +entry: +; CHECK-EL: addiu $sp, $sp +; CHECK-EL: .cfi_def_cfa_offset +; CHECK-EL: sdc1 $f20 +; CHECK-EL: sw $ra +; CHECK-EL: sw $17 +; CHECK-EL: sw $16 +; CHECK-EL: .cfi_offset 52, -8 +; CHECK-EL: .cfi_offset 53, -4 +; CHECK-EB: .cfi_offset 53, -8 +; CHECK-EB: .cfi_offset 52, -4 +; CHECK-EL: .cfi_offset 31, -12 +; CHECK-EL: .cfi_offset 17, -16 +; CHECK-EL: .cfi_offset 16, -20 +; CHECK-EL: .cprestore + + %exception = tail call i8* @__cxa_allocate_exception(i32 8) nounwind + %0 = bitcast i8* %exception to double* + store double 3.200000e+00, double* %0, align 8, !tbaa !0 + invoke void @__cxa_throw(i8* %exception, i8* bitcast (i8** @_ZTId to i8*), i8* null) noreturn + to label %unreachable unwind label %lpad + +lpad: ; preds = %entry +; CHECK-EL: # %lpad +; CHECK-EL: lw $gp +; CHECK-EL: beq $5 + + %exn = tail call i8* @llvm.eh.exception() nounwind + %eh.selector = tail call i32 (i8*, i8*, ...)* @llvm.eh.selector(i8* %exn, i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*), i8* bitcast (i8** @_ZTId to i8*)) nounwind + %1 = tail call i32 @llvm.eh.typeid.for(i8* bitcast (i8** @_ZTId to i8*)) nounwind + %2 = icmp eq i32 %eh.selector, %1 + br i1 %2, label %catch, label %eh.resume + +catch: ; preds = %lpad + %3 = tail call i8* @__cxa_begin_catch(i8* %exn) nounwind + %4 = bitcast i8* %3 to double* + %exn.scalar = load double* %4, align 8 + %add = fadd double %exn.scalar, %i2 + store double %add, double* @g1, align 8, !tbaa !0 + tail call void @__cxa_end_catch() nounwind + ret void + +eh.resume: ; preds = %lpad + tail call void @llvm.eh.resume(i8* %exn, i32 %eh.selector) noreturn + unreachable + +unreachable: ; preds = %entry + unreachable +} + +declare i8* @__cxa_allocate_exception(i32) + +declare i8* @llvm.eh.exception() nounwind readonly + +declare i32 @__gxx_personality_v0(...) + +declare i32 @llvm.eh.selector(i8*, i8*, ...) nounwind + +declare i32 @llvm.eh.typeid.for(i8*) nounwind + +declare void @llvm.eh.resume(i8*, i32) + +declare void @__cxa_throw(i8*, i8*, i8*) + +declare i8* @__cxa_begin_catch(i8*) + +declare void @__cxa_end_catch() + +!0 = metadata !{metadata !"double", metadata !1} +!1 = metadata !{metadata !"omnipotent char", metadata !2} +!2 = metadata !{metadata !"Simple C/C++ TBAA", null} -- 2.34.1