Fix an issue where the two-address conversion pass incorrectly rewrites untied

operands to an early clobber register. This fixes <rdar://problem/9566076>.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132738 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Cameron Zwarich 2011-06-07 23:54:00 +00:00
parent d846e3fb5a
commit aaa5f14d7c
2 changed files with 52 additions and 9 deletions

View File

@ -1125,6 +1125,7 @@ bool TwoAddressInstructionPass::runOnMachineFunction(MachineFunction &MF) {
break; // The tied operands have been eliminated.
}
bool IsEarlyClobber = false;
bool RemovedKillFlag = false;
bool AllUsesCopied = true;
unsigned LastCopiedReg = 0;
@ -1132,7 +1133,11 @@ bool TwoAddressInstructionPass::runOnMachineFunction(MachineFunction &MF) {
for (unsigned tpi = 0, tpe = TiedPairs.size(); tpi != tpe; ++tpi) {
unsigned SrcIdx = TiedPairs[tpi].first;
unsigned DstIdx = TiedPairs[tpi].second;
unsigned regA = mi->getOperand(DstIdx).getReg();
const MachineOperand &DstMO = mi->getOperand(DstIdx);
unsigned regA = DstMO.getReg();
IsEarlyClobber |= DstMO.isEarlyClobber();
// Grab regB from the instruction because it may have changed if the
// instruction was commuted.
regB = mi->getOperand(SrcIdx).getReg();
@ -1196,15 +1201,17 @@ bool TwoAddressInstructionPass::runOnMachineFunction(MachineFunction &MF) {
}
if (AllUsesCopied) {
// Replace other (un-tied) uses of regB with LastCopiedReg.
for (unsigned i = 0, e = mi->getNumOperands(); i != e; ++i) {
MachineOperand &MO = mi->getOperand(i);
if (MO.isReg() && MO.getReg() == regB && MO.isUse()) {
if (MO.isKill()) {
MO.setIsKill(false);
RemovedKillFlag = true;
if (!IsEarlyClobber) {
// Replace other (un-tied) uses of regB with LastCopiedReg.
for (unsigned i = 0, e = mi->getNumOperands(); i != e; ++i) {
MachineOperand &MO = mi->getOperand(i);
if (MO.isReg() && MO.getReg() == regB && MO.isUse()) {
if (MO.isKill()) {
MO.setIsKill(false);
RemovedKillFlag = true;
}
MO.setReg(LastCopiedReg);
}
MO.setReg(LastCopiedReg);
}
}

View File

@ -0,0 +1,36 @@
; RUN: llc < %s | FileCheck %s
target datalayout = "e-p:32:32:32-i1:8:32-i8:8:32-i16:16:32-i32:32:32-i64:32:32-f32:32:32-f64:32:32-v64:32:64-v128:32:128-a0:0:32-n32"
target triple = "thumbv7-apple-darwin10"
%struct.op = type { %struct.op*, %struct.op*, %struct.op* ()*, i32, i16, i16, i8, i8 }
; CHECK: Perl_ck_sort
; CHECK: ldr
; CHECK: mov [[REGISTER:(r[0-9]+)|(lr)]]
; CHECK: str {{(r[0-9])|(lr)}}, {{\[}}[[REGISTER]]{{\]}}, #24
define void @Perl_ck_sort() nounwind optsize {
entry:
%tmp27 = load %struct.op** undef, align 4
switch i16 undef, label %if.end151 [
i16 178, label %if.then60
i16 177, label %if.then60
]
if.then60: ; preds = %if.then40
br i1 undef, label %if.then67, label %if.end95
if.then67: ; preds = %if.then60
%op_next71 = getelementptr inbounds %struct.op* %tmp27, i32 0, i32 0
store %struct.op* %tmp27, %struct.op** %op_next71, align 4
%0 = getelementptr inbounds %struct.op* %tmp27, i32 1, i32 0
br label %if.end95
if.end95: ; preds = %if.else92, %if.then67
%.pre-phi = phi %struct.op** [ undef, %if.then60 ], [ %0, %if.then67 ]
%tmp98 = load %struct.op** %.pre-phi, align 4
br label %if.end151
if.end151: ; preds = %if.end100, %if.end, %entry
ret void
}