# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py # RUN: llc -mtriple aarch64 -run-pass=aarch64-post-select-optimize -verify-machineinstrs %s -o - | FileCheck %s --- | target datalayout = "e-m:o-i64:64-i128:128-n32:64-S128" @x = external hidden local_unnamed_addr global i32*, align 8 define void @copy_from_larger_rc_def() { ret void } define void @copy_from_larger_rc_def_multi_use() { ret void } define void @copy_from_smaller_rc_def() { ret void } ... --- name: copy_from_larger_rc_def alignment: 4 legalized: true regBankSelected: true selected: true tracksRegLiveness: true liveins: - { reg: '$x0' } - { reg: '$w1' } - { reg: '$x2' } body: | bb.1: liveins: $w1, $x0, $x2 ; Show that if we're doing a copy from a large rc to a single user with a smaller rc ; then we just constrain the def instead. ; CHECK-LABEL: name: copy_from_larger_rc_def ; CHECK: liveins: $w1, $x0, $x2 ; CHECK-NEXT: {{ $}} ; CHECK-NEXT: [[COPY:%[0-9]+]]:gpr64 = COPY $x0 ; CHECK-NEXT: %large_rc_def:gpr64common = UBFMXri [[COPY]], 61, 60 ; CHECK-NEXT: %add:gpr64sp = ADDXri %large_rc_def, 3, 0 ; CHECK-NEXT: $x0 = COPY %add ; CHECK-NEXT: RET_ReallyLR %0:gpr64 = COPY $x0 %large_rc_def:gpr64 = UBFMXri %0, 61, 60 %constrain_copy:gpr64common = COPY %large_rc_def ; Even though ADDXri may not actually need to use gpr64common, just use it as an example. %add:gpr64sp = ADDXri %constrain_copy, 3, 0 $x0 = COPY %add RET_ReallyLR ... --- name: copy_from_larger_rc_def_multi_use alignment: 4 legalized: true regBankSelected: true selected: true tracksRegLiveness: true liveins: - { reg: '$x0' } - { reg: '$w1' } - { reg: '$x2' } body: | bb.1: liveins: $w1, $x0, $x2 ; Don't constrain def if the original def has multiple users. ; CHECK-LABEL: name: copy_from_larger_rc_def_multi_use ; CHECK: liveins: $w1, $x0, $x2 ; CHECK-NEXT: {{ $}} ; CHECK-NEXT: [[COPY:%[0-9]+]]:gpr64 = COPY $x0 ; CHECK-NEXT: %large_rc_def:gpr64 = UBFMXri [[COPY]], 61, 60 ; CHECK-NEXT: %constrain_copy:gpr64common = COPY %large_rc_def ; CHECK-NEXT: %add:gpr64sp = ADDXri %constrain_copy, 3, 0 ; CHECK-NEXT: %add2:gpr64sp = ADDXri %constrain_copy, 3, 0 ; CHECK-NEXT: $x0 = COPY %add ; CHECK-NEXT: $x1 = COPY %large_rc_def ; CHECK-NEXT: RET_ReallyLR %0:gpr64 = COPY $x0 %large_rc_def:gpr64 = UBFMXri %0, 61, 60 %constrain_copy:gpr64common = COPY %large_rc_def %add:gpr64sp = ADDXri %constrain_copy, 3, 0 %add2:gpr64sp = ADDXri %constrain_copy, 3, 0 $x0 = COPY %add $x1 = COPY %large_rc_def RET_ReallyLR ... --- name: copy_from_smaller_rc_def alignment: 4 legalized: true regBankSelected: true selected: true tracksRegLiveness: true liveins: - { reg: '$x0' } - { reg: '$w1' } - { reg: '$x2' } body: | bb.1: liveins: $w1, $x0, $x2 ; Show that if we're doing a copy from a small rc to a single user with a larger rc ; then we just use the smaller def instead of doing a copy. ; CHECK-LABEL: name: copy_from_smaller_rc_def ; CHECK: liveins: $w1, $x0, $x2 ; CHECK-NEXT: {{ $}} ; CHECK-NEXT: [[COPY:%[0-9]+]]:gpr64common = COPY $x0 ; CHECK-NEXT: [[COPY1:%[0-9]+]]:gpr64common = COPY $x1 ; CHECK-NEXT: %add:gpr64common = ADDXri [[COPY1]], 3, 0 ; CHECK-NEXT: STRXui [[COPY1]], %add, target-flags(aarch64-pageoff, aarch64-nc) @x :: (store (p0)) ; CHECK-NEXT: RET_ReallyLR %0:gpr64common = COPY $x0 %1:gpr64common = COPY $x1 %add:gpr64common = ADDXri %1, 3, 0 %copy:gpr64sp = COPY %add STRXui %1, %copy, target-flags(aarch64-pageoff, aarch64-nc) @x :: (store (p0)) RET_ReallyLR ...