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.
 
 

llvm-svn: 132703
This commit is contained in:
Akira Hatanaka 2011-06-07 02:17:21 +00:00
parent 6575812c48
commit fbeb14925f
2 changed files with 138 additions and 30 deletions

View File

@ -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<MachineMove> &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<CalleeSavedInfo> &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<CalleeSavedInfo>::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<MachineMove> &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<CalleeSavedInfo>::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,

78
test/CodeGen/Mips/eh.ll Normal file
View File

@ -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}