# RUN: llc -mtriple amdgcn -run-pass livevars -run-pass phi-node-elimination -o - %s | FileCheck %s
# RUN: llc -mtriple amdgcn --passes='require<live-vars>,phi-node-elimination' -o - %s | FileCheck %s
################################################################################
# This test used to hit an assert in PHIElimination:
# PHIElimination::LowerPHINode(llvm::MachineBasicBlock&, llvm::MachineBasicBlock::iterator): Assertion `KillInst->readsRegister(SrcReg) && "Cannot find kill instruction"'
---
name: foo
tracksRegLiveness: true
body: |
bb.0:
S_CBRANCH_SCC0 %bb.2, implicit undef $scc
bb.1:
%1:sreg_32_xm0 = S_MOV_B32 255
S_BRANCH %bb.3
bb.2:
%2:sreg_32_xm0 = S_MOV_B32 254
bb.3:
dead %3:sreg_32_xm0 = PHI undef %2, %bb.2, undef %1, %bb.1
%4:sreg_32_xm0 = PHI %2, %bb.2, %1, %bb.1
S_NOP 0, implicit %4
...
# CHECK-LABEL: name: foo
# CHECK: bb.3:
# CHECK-NEXT: dead %2:sreg_32_xm0 = IMPLICIT_DEF
# CHECK-NEXT: %3:sreg_32_xm0 = COPY killed %4
# CHECK-NEXT: S_NOP 0, implicit killed %3
################################################################################
# Similar test as above, but with swapped order for the PHI nodes.
# With this PHI node order we did not hit the assert, but we used to get
#
# bb.3:
# dead %3:sreg_32_xm0 = COPY killed %4
# %2:sreg_32_xm0 = COPY %4
# S_NOP 0, implicit killed %2
#
# which looks weird regarding killed flags for %4.
---
name: bar
tracksRegLiveness: true
body: |
bb.0:
S_CBRANCH_SCC0 %bb.2, implicit undef $scc
bb.1:
%1:sreg_32_xm0 = S_MOV_B32 255
S_BRANCH %bb.3
bb.2:
%2:sreg_32_xm0 = S_MOV_B32 254
bb.3:
%4:sreg_32_xm0 = PHI %2, %bb.2, %1, %bb.1
dead %3:sreg_32_xm0 = PHI undef %2, %bb.2, undef %1, %bb.1
S_NOP 0, implicit %4
...
# CHECK-LABEL: name: bar
# CHECK: bb.3:
# CHECK-NEXT: dead %3:sreg_32_xm0 = IMPLICIT_DEF
# CHECK-NEXT: %2:sreg_32_xm0 = COPY killed %4
# CHECK-NEXT: S_NOP 0, implicit killed %2
# The following test crashes in phi-elimination hooks.
#
---
name: bax
tracksRegLiveness: true
body: |
bb.0:
S_CBRANCH_SCC0 %bb.2, implicit undef $scc
bb.1:
%1:sreg_32_xm0 = S_MOV_B32 255
S_BRANCH %bb.3
bb.2:
%2:sreg_32_xm0 = S_MOV_B32 254
bb.3:
%3:sreg_32_xm0 = PHI %2, %bb.2, %1, %bb.1
...
# CHECK-LABEL: name: bax
# CHECK: bb.3:
# CHECK-NEXT: %2:sreg_32_xm0 = COPY killed %3
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