# RUN: llc -mtriple=x86_64-unknown-linux-gnu -run-pass=register-coalescer -o - %s
# An implicit-def will be added to SUBREG_TO_REG during coalescing
---
name: rematerialize_subreg_to_reg_added_impdef_0
tracksRegLiveness: true
body: |
bb.0:
successors: %bb.1(0x2aaaaaab), %bb.2(0x55555555)
liveins: $edi
%0:gr32 = MOV32r0 implicit-def dead $eflags
%1:gr8 = COPY %0.sub_8bit
%2:gr64 = SUBREG_TO_REG 0, killed %0, %subreg.sub_32bit
JCC_1 %bb.2, 5, implicit killed undef $eflags
bb.1:
%4:gr8 = COPY %1
%5:gr8 = COPY killed undef %1
JMP_1 %bb.5
bb.2:
%6:gr64 = IMPLICIT_DEF
%2:gr64 = COPY killed %6
%5:gr8 = MOV8ri 1
bb.5:
successors: %bb.6(0x30000000), %bb.7(0x50000000)
TEST8rr killed undef %5, %5, implicit-def $eflags
JCC_1 %bb.7, 5, implicit killed undef $eflags
bb.6:
$al = COPY killed %1
RET 0, killed undef $al
bb.7:
MOV64mr undef $noreg, 1, undef $noreg, 0, undef $noreg, killed %2 :: (store (s64))
RET 0, killed undef $al
...
# Reduced version of previous with the SUBREG_TO_REG already folded
# away.
#
# The mov32r0 defines a subregister and has an implicit-def of the
# super register. After coalescing, the full register implicit def of
# %2 becomes a different subregister def.
---
name: rematerialize_subreg_to_reg_coalesces_to_subreg_impdef
tracksRegLiveness: true
body: |
bb.0:
successors: %bb.1(0x2aaaaaab), %bb.2(0x55555555)
liveins: $edi
undef %2.sub_32bit:gr64_with_sub_8bit = MOV32r0 implicit-def dead $eflags, implicit-def %2
%1:gr8 = COPY %2.sub_8bit
JCC_1 %bb.2, 5, implicit killed undef $eflags
bb.1:
successors: %bb.3(0x80000000)
dead %3:gr8 = COPY %1
%4:gr8 = COPY undef %1
JMP_1 %bb.3
bb.2:
successors: %bb.3(0x80000000)
%5:gr64 = IMPLICIT_DEF
%2:gr64_with_sub_8bit = COPY %5
%4:gr8 = MOV8ri 1
bb.3:
successors: %bb.4(0x30000000), %bb.5(0x50000000)
TEST8rr undef %4, %4, implicit-def $eflags
JCC_1 %bb.5, 5, implicit killed undef $eflags
bb.4:
$al = COPY %1
RET 0, killed undef $al
bb.5:
MOV64mr undef $noreg, 1, undef $noreg, 0, undef $noreg, %2 :: (store (s64))
RET 0, killed undef $al
...
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