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| # RUN: llc -o - %s -mtriple=aarch64-- -mattr=+arith-bcc-fusion -run-pass postmisched | FileCheck %s --check-prefixes=CHECK,FUSION
# RUN: llc -o - %s -mtriple=aarch64-- -mattr=-arith-bcc-fusion -run-pass postmisched | FileCheck %s --check-prefixes=CHECK,NOFUSION
# Make sure the last instruction is correctly macro-fused when scheduling
# top-down (post-ra).
---
# CHECK-LABEL: name: fuse_last
# CHECK: $x1 = LDRXui $x0, 0
# NOFUSION: $xzr = SUBSXri killed $x2, 0, 0, implicit-def $nzcv
# CHECK: STRXui killed $x0, killed $x1, 0
# FUSION: $xzr = SUBSXri killed $x2, 0, 0, implicit-def $nzcv
# CHECK: Bcc 1, %bb.1, implicit killed $nzcv
name: fuse_last
tracksRegLiveness: true
body: |
bb.0:
liveins: $x0, $x2
$x1 = LDRXui $x0, 0
; There is latency between these two instructions tempting the scheduler to
; move the SUBSXri in between them. However doing so breaks macro fusion.
STRXui $x0, $x1, 0
$xzr = SUBSXri $x2, 0, 0, implicit-def $nzcv
Bcc 1, %bb.1, implicit killed $nzcv
bb.1:
RET_ReallyLR implicit undef $x0
...
|