ARM: Fix more fast-isel verifier failures.

Teach the generic instruction selection helper functions to constrain
the register classes of their input operands. For non-physical register
references, the generic code needs to be careful not to mess that up
when replacing references to result registers. As the comment indicates
for MachineRegisterInfo::replaceRegWith(), it's important to call
constrainRegClass() first.

rdar://12594152

llvm-svn: 188593
This commit is contained in:
Jim Grosbach 2013-08-16 23:37:31 +00:00
parent d69f3ed947
commit 06c2a68125
3 changed files with 48 additions and 1 deletions

View File

@ -497,6 +497,10 @@ bool SelectionDAGISel::runOnMachineFunction(MachineFunction &mf) {
if (J == E) break;
To = J->second;
}
// Make sure the new register has a sufficiently constrained register class.
if (TargetRegisterInfo::isVirtualRegister(From) &&
TargetRegisterInfo::isVirtualRegister(To))
MRI.constrainRegClass(To, MRI.getRegClass(From));
// Replace it.
MRI.replaceRegWith(From, To);
}

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@ -176,6 +176,8 @@ class ARMFastISel : public FastISel {
// Utility routines.
private:
unsigned constrainOperandRegClass(const MCInstrDesc &II, unsigned OpNum,
unsigned Op);
bool isTypeLegal(Type *Ty, MVT &VT);
bool isLoadTypeLegal(Type *Ty, MVT &VT);
bool ARMEmitCmp(const Value *Src1Value, const Value *Src2Value,
@ -291,6 +293,23 @@ ARMFastISel::AddOptionalDefs(const MachineInstrBuilder &MIB) {
return MIB;
}
unsigned ARMFastISel::constrainOperandRegClass(const MCInstrDesc &II,
unsigned Op, unsigned OpNum) {
if (TargetRegisterInfo::isVirtualRegister(Op)) {
const TargetRegisterClass *RegClass =
TII.getRegClass(II, OpNum, &TRI, *FuncInfo.MF);
if (!MRI.constrainRegClass(Op, RegClass)) {
// If it's not legal to COPY between the register classes, something
// has gone very wrong before we got here.
unsigned NewOp = createResultReg(RegClass);
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(TargetOpcode::COPY), NewOp).addReg(Op));
return NewOp;
}
}
return Op;
}
unsigned ARMFastISel::FastEmitInst_(unsigned MachineInstOpcode,
const TargetRegisterClass* RC) {
unsigned ResultReg = createResultReg(RC);
@ -306,6 +325,9 @@ unsigned ARMFastISel::FastEmitInst_r(unsigned MachineInstOpcode,
unsigned ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
// Make sure the input operand is sufficiently constrained to be legal
// for this instruction.
Op0 = constrainOperandRegClass(II, Op0, 1);
if (II.getNumDefs() >= 1) {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill));
@ -326,6 +348,11 @@ unsigned ARMFastISel::FastEmitInst_rr(unsigned MachineInstOpcode,
unsigned ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
// Make sure the input operands are sufficiently constrained to be legal
// for this instruction.
Op0 = constrainOperandRegClass(II, Op0, 1);
Op1 = constrainOperandRegClass(II, Op1, 2);
if (II.getNumDefs() >= 1) {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill)
@ -349,6 +376,12 @@ unsigned ARMFastISel::FastEmitInst_rrr(unsigned MachineInstOpcode,
unsigned ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
// Make sure the input operands are sufficiently constrained to be legal
// for this instruction.
Op0 = constrainOperandRegClass(II, Op0, 1);
Op1 = constrainOperandRegClass(II, Op1, 2);
Op2 = constrainOperandRegClass(II, Op1, 3);
if (II.getNumDefs() >= 1) {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill)
@ -373,6 +406,9 @@ unsigned ARMFastISel::FastEmitInst_ri(unsigned MachineInstOpcode,
unsigned ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
// Make sure the input operand is sufficiently constrained to be legal
// for this instruction.
Op0 = constrainOperandRegClass(II, Op0, 1);
if (II.getNumDefs() >= 1) {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill)
@ -395,6 +431,9 @@ unsigned ARMFastISel::FastEmitInst_rf(unsigned MachineInstOpcode,
unsigned ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
// Make sure the input operand is sufficiently constrained to be legal
// for this instruction.
Op0 = constrainOperandRegClass(II, Op0, 1);
if (II.getNumDefs() >= 1) {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill)
@ -418,6 +457,10 @@ unsigned ARMFastISel::FastEmitInst_rri(unsigned MachineInstOpcode,
unsigned ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
// Make sure the input operands are sufficiently constrained to be legal
// for this instruction.
Op0 = constrainOperandRegClass(II, Op0, 1);
Op1 = constrainOperandRegClass(II, Op1, 2);
if (II.getNumDefs() >= 1) {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill)

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@ -1,6 +1,6 @@
; RUN: llc < %s -O0 -fast-isel-abort -relocation-model=dynamic-no-pic -mtriple=armv7-apple-ios -verify-machineinstrs | FileCheck %s --check-prefix=ARM
; RUN: llc < %s -O0 -fast-isel-abort -relocation-model=dynamic-no-pic -mtriple=armv7-linux-gnueabi -verify-machineinstrs | FileCheck %s --check-prefix=ARM
; RUN: llc < %s -O0 -fast-isel-abort -relocation-model=dynamic-no-pic -mtriple=thumbv7-apple-ios | FileCheck %s --check-prefix=THUMB
; RUN: llc < %s -O0 -fast-isel-abort -relocation-model=dynamic-no-pic -mtriple=thumbv7-apple-ios -verify-machineinstrs | FileCheck %s --check-prefix=THUMB
; Very basic fast-isel functionality.
define i32 @test0(i32 %a, i32 %b) nounwind {