test/CodeGen/AArch64/machine-dead-copy.mir

# RUN: llc -mtriple=aarch64-none-linux-gnu -run-pass machine-cp  -verify-machineinstrs  -o - %s | FileCheck %s

--- |
  define i32 @copyprop1(i32 %a, i32 %b) { ret i32 %a }
  define i32 @copyprop2(i32 %a, i32 %b) { ret i32 %a }
  define i32 @copyprop3(i32 %a, i32 %b) { ret i32 %a }
  define i32 @copyprop4(i32 %a, i32 %b) { ret i32 %a }
  declare i32 @foo(i32)
...
---
# The first copy is dead copy which is not used.
# CHECK-LABEL: name: copyprop1
# CHECK: bb.0:
# CHECK-NOT: %w20 = COPY
name: copyprop1
body: |
  bb.0:
    liveins: %w0,  %w1
    %w20 = COPY %w1
    BL @foo, csr_aarch64_aapcs, implicit %w0, implicit-def %w0
    RET_ReallyLR implicit %w0
...
---
# The first copy is not a dead copy which is used in the second copy after the
# call.
# CHECK-LABEL: name: copyprop2
# CHECK: bb.0:
# CHECK: %w20 = COPY
name: copyprop2
body: |
  bb.0:
    liveins: %w0,  %w1
    %w20 = COPY %w1
    BL @foo, csr_aarch64_aapcs, implicit %w0, implicit-def %w0
    %w0 = COPY %w20
    RET_ReallyLR implicit %w0
...
---
# Both the first and second copy are dead copies which are not used.
# CHECK-LABEL: name: copyprop3
# CHECK: bb.0:
# CHECK-NOT: COPY
name: copyprop3
body: |
  bb.0:
    liveins: %w0,  %w1
    %w20 = COPY %w1
    BL @foo, csr_aarch64_aapcs, implicit %w0, implicit-def %w0
    %w20 = COPY %w0
    RET_ReallyLR implicit %w0
...
# The second copy is removed as a NOP copy, after then the first copy become
# dead which should be removed as well.
# CHECK-LABEL: name: copyprop4
# CHECK: bb.0:
# CHECK-NOT: COPY
name: copyprop4
body: |
  bb.0:
    liveins: %w0,  %w1
    %w20 = COPY %w0
    %w0 = COPY %w20
    BL @foo, csr_aarch64_aapcs, implicit %w0, implicit-def %w0
    RET_ReallyLR implicit %w0
...