[AArch64] Add MMOs to callee-save load/store instructions.

Summary:
Without MMOs, the callee-save load/store instructions were treated as
volatile by the MI post-RA scheduler and AArch64LoadStoreOptimizer.

Reviewers: t.p.northover, mcrosier

Subscribers: aemerson, rengolin, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D17661

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266439 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Geoff Berry 2016-04-15 15:16:19 +00:00
parent fb9467aca8
commit 82ae2982d4
2 changed files with 38 additions and 2 deletions

View File

@ -871,6 +871,9 @@ bool AArch64FrameLowering::spillCalleeSavedRegisters(
.addReg(AArch64::SP)
.addImm(Offset) // [sp, #offset * 8], where factor * 8 is implicit
.setMIFlag(MachineInstr::FrameSetup);
MIB.addMemOperand(MF.getMachineMemOperand(
MachinePointerInfo::getFixedStack(MF, RPI.FrameIdx + 1),
MachineMemOperand::MOStore, 8, 8));
} else {
MBB.addLiveIn(Reg1);
MIB.addReg(Reg1, getPrologueDeath(MF, Reg1))
@ -878,6 +881,9 @@ bool AArch64FrameLowering::spillCalleeSavedRegisters(
.addImm(BumpSP ? Offset * 8 : Offset) // pre-inc version is unscaled
.setMIFlag(MachineInstr::FrameSetup);
}
MIB.addMemOperand(MF.getMachineMemOperand(
MachinePointerInfo::getFixedStack(MF, RPI.FrameIdx),
MachineMemOperand::MOStore, 8, 8));
}
return true;
}
@ -935,19 +941,26 @@ bool AArch64FrameLowering::restoreCalleeSavedRegisters(
if (BumpSP)
MIB.addReg(AArch64::SP, RegState::Define);
if (RPI.isPaired())
if (RPI.isPaired()) {
MIB.addReg(Reg2, getDefRegState(true))
.addReg(Reg1, getDefRegState(true))
.addReg(AArch64::SP)
.addImm(Offset) // [sp], #offset * 8 or [sp, #offset * 8]
// where the factor * 8 is implicit
.setMIFlag(MachineInstr::FrameDestroy);
else
MIB.addMemOperand(MF.getMachineMemOperand(
MachinePointerInfo::getFixedStack(MF, RPI.FrameIdx + 1),
MachineMemOperand::MOLoad, 8, 8));
} else {
MIB.addReg(Reg1, getDefRegState(true))
.addReg(AArch64::SP)
.addImm(BumpSP ? Offset * 8 : Offset) // post-dec version is unscaled
.setMIFlag(MachineInstr::FrameDestroy);
}
MIB.addMemOperand(MF.getMachineMemOperand(
MachinePointerInfo::getFixedStack(MF, RPI.FrameIdx),
MachineMemOperand::MOLoad, 8, 8));
}
return true;
}

View File

@ -0,0 +1,23 @@
; RUN: llc < %s -mtriple=arm64-linux-gnu -mcpu=cortex-a57 -enable-misched=0 -debug-only=misched -o - 2>&1 > /dev/null | FileCheck %s
@G = external global [0 x i32], align 4
; Check that MMOs are added to epilogue calle-save restore loads so
; that the store to G is not considered dependant on the callee-save
; loads.
;
; CHECK: Before post-MI-sched:
; CHECK-LABEL: # Machine code for function test1:
; CHECK: SU(2): STRWui %WZR
; CHECK: SU(3): %X21<def>, %X20<def> = LDPXi %SP
; CHECK: Predecessors:
; CHECK-NEXT: out SU(0)
; CHECK-NEXT: out SU(0)
; CHECK-NEXT: ch SU(0)
; CHECK-NEXT: Successors:
define void @test1() {
entry:
tail call void asm sideeffect "nop", "~{x20},~{x21},~{x22},~{x23}"() nounwind
store i32 0, i32* getelementptr inbounds ([0 x i32], [0 x i32]* @G, i64 0, i64 0), align 4
ret void
}