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| # RUN: llc -run-pass=peephole-opt %s -o - | FileCheck %s
# Here we check that the peephole cmp rewrite is not triggered, because
# there is store instruction between the tMUL and tCMP, i.e. there are
# no constants to reorder.
--- |
; ModuleID = 'cmp2-peephole-thumb.ll'
source_filename = "<stdin>"
target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
target triple = "thumb-none--eabi"
define i32 @g(i32 %a, i32 %b) {
entry:
%retval = alloca i32, align 4
%mul = alloca i32, align 4
%mul1 = mul nsw i32 %a, %b
store i32 %mul1, i32* %mul, align 4
%0 = load i32, i32* %mul, align 4
%cmp = icmp sle i32 %0, 0
br i1 %cmp, label %if.then, label %if.end
if.then: ; preds = %entry
store i32 42, i32* %retval, align 4
br label %return
if.end: ; preds = %entry
store i32 1, i32* %retval, align 4
br label %return
return: ; preds = %if.end, %if.then
%1 = load i32, i32* %retval, align 4
ret i32 %1
}
...
---
name: g
# CHECK-LABEL: name: g
alignment: 2
exposesReturnsTwice: false
legalized: false
regBankSelected: false
selected: false
tracksRegLiveness: true
registers:
- { id: 0, class: tgpr }
- { id: 1, class: tgpr }
- { id: 2, class: tgpr }
- { id: 3, class: tgpr }
- { id: 4, class: tgpr }
- { id: 5, class: tgpr }
liveins:
- { reg: '$r0', virtual-reg: '%0' }
- { reg: '$r1', virtual-reg: '%1' }
frameInfo:
isFrameAddressTaken: false
isReturnAddressTaken: false
hasStackMap: false
hasPatchPoint: false
stackSize: 0
offsetAdjustment: 0
maxAlignment: 4
adjustsStack: false
hasCalls: false
maxCallFrameSize: 0
hasOpaqueSPAdjustment: false
hasVAStart: false
hasMustTailInVarArgFunc: false
stack:
- { id: 0, name: retval, offset: 0, size: 4, alignment: 4, local-offset: -4 }
- { id: 1, name: mul, offset: 0, size: 4, alignment: 4, local-offset: -8 }
# CHECK: tMUL
# CHECK-NEXT: tSTRspi
# CHECK-NEXT: tCMPi8
body: |
bb.0.entry:
liveins: $r0, $r1
%1 = COPY $r1
%0 = COPY $r0
%2, $cpsr = tMUL %0, %1, 14, $noreg
tSTRspi %2, %stack.1.mul, 0, 14, $noreg :: (store 4 into %ir.mul)
tCMPi8 %2, 0, 14, $noreg, implicit-def $cpsr
tBcc %bb.2.if.end, 12, $cpsr
tB %bb.1.if.then, 14, $noreg
bb.1.if.then:
%4, $cpsr = tMOVi8 42, 14, $noreg
tSTRspi killed %4, %stack.0.retval, 0, 14, $noreg :: (store 4 into %ir.retval)
tB %bb.3.return, 14, $noreg
bb.2.if.end:
%3, $cpsr = tMOVi8 1, 14, $noreg
tSTRspi killed %3, %stack.0.retval, 0, 14, $noreg :: (store 4 into %ir.retval)
bb.3.return:
%5 = tLDRspi %stack.0.retval, 0, 14, $noreg :: (dereferenceable load 4 from %ir.retval)
$r0 = COPY %5
tBX_RET 14, $noreg, implicit $r0
...
|