llvm/test/CodeGen/X86/two-address-subreg-to-reg-kill.mir

# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 6
# RUN: llc -mtriple=x86_64-unknown-linux-gnu --run-pass=livevars,twoaddressinstruction %s -o - | FileCheck %s

# Positive case: IMUL32rm with %1 as a tied source should be hoisted 
# before the pass, subreg_to_reg kills a 32-bit vreg (%1) and writes to
# physical $eax, which allows IMUL32rm can use %eax.
---
name: subreg_to_reg_kill_hoist
tracksRegLiveness: true
registers:
  - { id: 0, class: gr64 }
  - { id: 1, class: gr32 }
  - { id: 2, class: gr32 }
liveins:
  - { reg: '$rdi', virtual-reg: '%0' }
  - { reg: '$esi', virtual-reg: '%1' }
body: |
  bb.0:
    liveins: $rdi, $esi

    ; CHECK-LABEL: name: subreg_to_reg_kill_hoist
    ; CHECK: [[COPY1:%[0-9]+]]:gr32 = COPY killed $esi
    ; CHECK-NEXT: dead $rax = SUBREG_TO_REG [[COPY1]], %subreg.sub_32bit
    ; CHECK: IMUL32rm
    %0:gr64 = COPY killed $rdi
    %1:gr32 = COPY killed $esi
    dead %2:gr32 = IMUL32rm %1, %0, 1, $noreg, 4, $noreg, implicit-def dead $eflags :: (load (s32) from `ptr undef`, align 4)
    dead $rax = SUBREG_TO_REG killed %1, %subreg.sub_32bit
    RET 0

---
# Negative case: subreg_to_reg with a vreg is not hoisted.
# The pass keeps the IMUL32rm as is and MOV32rm + IMUL32rr is emitted instead.
name: subreg_to_reg_virtual_dst_no_hoist
tracksRegLiveness: true
registers:
  - { id: 0, class: gr64 }
  - { id: 1, class: gr32 }
  - { id: 2, class: gr32 }
  - { id: 3, class: gr64 }
liveins:
  - { reg: '$rdi', virtual-reg: '%0' }
  - { reg: '$esi', virtual-reg: '%1' }
body: |
  bb.0:
    liveins: $rdi, $esi

    ; CHECK-LABEL: name: subreg_to_reg_virtual_dst_no_hoist
    ; CHECK: MOV32rm
    ; CHECK-NEXT: [[COPY2:%[0-9]+]]:gr32 = COPY
    ; CHECK-NEXT: dead [[COPY2]]:gr32 = IMUL32rr [[COPY2]], %1, implicit-def dead $eflags
    %0:gr64 = COPY killed $rdi
    %1:gr32 = COPY killed $esi
    dead %2:gr32 = IMUL32rm %1, %0, 1, $noreg, 4, $noreg, implicit-def dead $eflags :: (load (s32) from `ptr undef`, align 4)
    dead %3:gr64 = SUBREG_TO_REG killed %1, %subreg.sub_32bit
    RET 0

---
# Positive case: COPY to a physical register is hoisted above IMUL32rm.
name: copy_kill_hoist
tracksRegLiveness: true
registers:
  - { id: 0, class: gr64 }
  - { id: 1, class: gr32 }
  - { id: 2, class: gr32 }
liveins:
  - { reg: '$rdi', virtual-reg: '%0' }
  - { reg: '$esi', virtual-reg: '%1' }
body: |
  bb.0:
    liveins: $rdi, $esi

    ; CHECK-LABEL: name: copy_kill_hoist
    ; CHECK: [[COPY1:%[0-9]+]]:gr32 = COPY killed $esi
    ; CHECK-NEXT: dead $eax = COPY [[COPY1]]
    ; CHECK: IMUL32rm
    %0:gr64 = COPY killed $rdi
    %1:gr32 = COPY killed $esi
    dead %2:gr32 = IMUL32rm %1, %0, 1, $noreg, 4, $noreg, implicit-def dead $eflags :: (load (s32) from `ptr undef`, align 4)
    dead $eax = COPY killed %1
    RET 0

---
# Negative case: COPY with a vreg destination is not hoisted.
name: copy_virtual_dst_no_hoist
tracksRegLiveness: true
registers:
  - { id: 0, class: gr64 }
  - { id: 1, class: gr32 }
  - { id: 2, class: gr32 }
  - { id: 3, class: gr32 }
liveins:
  - { reg: '$rdi', virtual-reg: '%0' }
  - { reg: '$esi', virtual-reg: '%1' }
body: |
  bb.0:
    liveins: $rdi, $esi

    ; CHECK-LABEL: name: copy_virtual_dst_no_hoist
    ; CHECK: MOV32rm
    ; CHECK-NEXT: [[COPY2:%[0-9]+]]:gr32 = COPY
    ; CHECK-NEXT: dead [[COPY2]]:gr32 = IMUL32rr [[COPY2]], %1, implicit-def dead $eflags
    %0:gr64 = COPY killed $rdi
    %1:gr32 = COPY killed $esi
    dead %2:gr32 = IMUL32rm %1, %0, 1, $noreg, 4, $noreg, implicit-def dead $eflags :: (load (s32) from `ptr undef`, align 4)
    dead %3:gr32 = COPY killed %1
    RET 0
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