test/CodeGen/AArch64/GlobalISel/fold-global-offsets.mir

# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
# RUN: llc -mtriple aarch64-apple-darwin -run-pass=aarch64-prelegalizer-combiner -verify-machineinstrs %s -o - | FileCheck %s

--- |
    @g = external hidden global i32

    %opaque = type opaque
    @unsized = external hidden global %opaque

    define void @one_ptr_add() { ret void }
    define void @add_to_offset() { ret void }
    define void @two_ptr_adds_same_offset() { ret void }
    define void @two_ptr_adds_different_offset() { ret void }
    define void @ptr_add_chain() { ret void }

    define void @dont_fold_negative_offset() { ret void }
    define void @dont_min_offset_less_than_curr_offset() { ret void }
    define void @dont_fold_max_offset() { ret void }
    define void @dont_fold_offset_larger_than_type_alloc() { ret void }
    define void @dont_fold_unsized_type() { ret void }
...
---
name:            one_ptr_add
alignment:       4
tracksRegLiveness: true
machineFunctionInfo: {}
body:             |
  bb.0:
    liveins: $x0

    ; We should fold the offset 1 into the G_GLOBAL_VALUE.

    ; CHECK-LABEL: name: one_ptr_add
    ; CHECK: liveins: $x0
    ; CHECK: [[GV:%[0-9]+]]:_(p0) = G_GLOBAL_VALUE @g + 1
    ; CHECK: $x0 = COPY [[GV]](p0)
    ; CHECK: RET_ReallyLR implicit $x0
    %global:_(p0) = G_GLOBAL_VALUE @g
    %offset:_(s64) = G_CONSTANT i64 1
    %ptr_add:_(p0) = G_PTR_ADD %global, %offset(s64)
    $x0 = COPY %ptr_add
    RET_ReallyLR implicit $x0

...
---
name:            add_to_offset
alignment:       4
tracksRegLiveness: true
machineFunctionInfo: {}
body:             |
  bb.0:
    liveins: $x0

    ; We should fold the offset 1 into the G_GLOBAL_VALUE, resulting in a
    ; final offset of 4.

    ; CHECK-LABEL: name: add_to_offset
    ; CHECK: liveins: $x0
    ; CHECK: [[GV:%[0-9]+]]:_(p0) = G_GLOBAL_VALUE @g + 4
    ; CHECK: $x0 = COPY [[GV]](p0)
    ; CHECK: RET_ReallyLR implicit $x0
    %global:_(p0) = G_GLOBAL_VALUE @g + 3
    %offset:_(s64) = G_CONSTANT i64 1
    %ptr_add:_(p0) = G_PTR_ADD %global, %offset(s64)
    $x0 = COPY %ptr_add
    RET_ReallyLR implicit $x0

...
---
name:            two_ptr_adds_same_offset
alignment:       4
tracksRegLiveness: true
machineFunctionInfo: {}
body:             |
  bb.0:
    liveins: $x0, $x1

    ; We're allowed to have more than one G_PTR_ADD use. We should fold 1 into
    ; the G_GLOBAL_VALUE's offset.

    ; CHECK-LABEL: name: two_ptr_adds_same_offset
    ; CHECK: liveins: $x0, $x1
    ; CHECK: %val1:_(s64) = COPY $x0
    ; CHECK: %val2:_(s64) = COPY $x1
    ; CHECK: [[GV:%[0-9]+]]:_(p0) = G_GLOBAL_VALUE @g + 1
    ; CHECK: G_STORE %val1(s64), [[GV]](p0) :: (store 8)
    ; CHECK: G_STORE %val2(s64), [[GV]](p0) :: (store 8)
    ; CHECK: RET_ReallyLR implicit $x0
    %val1:_(s64) = COPY $x0
    %val2:_(s64) = COPY $x1
    %global:_(p0) = G_GLOBAL_VALUE @g
    %offset:_(s64) = G_CONSTANT i64 1
    %ptr_add1:_(p0) = G_PTR_ADD %global, %offset(s64)
    %ptr_add2:_(p0) = G_PTR_ADD %global, %offset(s64)
    G_STORE %val1:_(s64), %ptr_add1 :: (store 8)
    G_STORE %val2:_(s64), %ptr_add2 :: (store 8)
    RET_ReallyLR implicit $x0

...
---
name:            two_ptr_adds_different_offset
alignment:       4
tracksRegLiveness: true
machineFunctionInfo: {}
body:             |
  bb.0:
    liveins: $x0, $x1
    ; The lowest offset G_PTR_ADD (2) should be folded into the G_GLOBAL_VALUE.
    ;
    ; The other G_PTR_ADD should have its offset decremented by 2.

    ; CHECK-LABEL: name: two_ptr_adds_different_offset
    ; CHECK: liveins: $x0, $x1
    ; CHECK: %val1:_(s64) = COPY $x0
    ; CHECK: %val2:_(s64) = COPY $x1
    ; CHECK: [[GV:%[0-9]+]]:_(p0) = G_GLOBAL_VALUE @g + 2
    ; CHECK: [[C:%[0-9]+]]:_(s64) = G_CONSTANT i64 8
    ; CHECK: %ptr_add2:_(p0) = G_PTR_ADD [[GV]], [[C]](s64)
    ; CHECK: G_STORE %val1(s64), [[GV]](p0) :: (store 8)
    ; CHECK: G_STORE %val2(s64), %ptr_add2(p0) :: (store 8)
    ; CHECK: RET_ReallyLR implicit $x0
    %val1:_(s64) = COPY $x0
    %val2:_(s64) = COPY $x1
    %global:_(p0) = G_GLOBAL_VALUE @g
    %offset1:_(s64) = G_CONSTANT i64 2
    %offset2:_(s64) = G_CONSTANT i64 10
    %ptr_add1:_(p0) = G_PTR_ADD %global, %offset1(s64)
    %ptr_add2:_(p0) = G_PTR_ADD %global, %offset2(s64)
    G_STORE %val1:_(s64), %ptr_add1 :: (store 8)
    G_STORE %val2:_(s64), %ptr_add2 :: (store 8)
    RET_ReallyLR implicit $x0

...
---
name:            ptr_add_chain
alignment:       4
tracksRegLiveness: true
machineFunctionInfo: {}
body:             |
  bb.0:
    liveins: $x0
    ; We should be able to fold all of the G_PTR_ADDs, except for the last one
    ; into the G_GLOBAL_VALUE.
    ;
    ; (TypeAllocSize = 4, so the offset on the G_GLOBAL_VALUE can't go above
    ; that.)

    ; CHECK-LABEL: name: ptr_add_chain
    ; CHECK: liveins: $x0
    ; CHECK: [[GV:%[0-9]+]]:_(p0) = G_GLOBAL_VALUE @g + 1
    ; CHECK: [[C:%[0-9]+]]:_(s64) = G_CONSTANT i64 4
    ; CHECK: %dont_fold_me:_(p0) = G_PTR_ADD [[GV]], [[C]](s64)
    ; CHECK: $x0 = COPY %dont_fold_me(p0)
    ; CHECK: RET_ReallyLR implicit $x0
    %global:_(p0) = G_GLOBAL_VALUE @g
    %offset:_(s64) = G_CONSTANT i64 1
    %ptr_add1:_(p0) = G_PTR_ADD %global, %offset(s64)
    %ptr_add2:_(p0) = G_PTR_ADD %ptr_add1, %offset(s64)
    %ptr_add3:_(p0) = G_PTR_ADD %ptr_add2, %offset(s64)
    %ptr_add4:_(p0) = G_PTR_ADD %ptr_add3, %offset(s64)
    %dont_fold_me:_(p0) = G_PTR_ADD %ptr_add4, %offset(s64)
    $x0 = COPY %dont_fold_me
    RET_ReallyLR implicit $x0

...
---
name:            dont_fold_negative_offset
alignment:       4
tracksRegLiveness: true
machineFunctionInfo: {}
body:             |
  bb.0:
    liveins: $x0

    ; Do not add negative offsets to G_GLOBAL_VALUE.

    ; CHECK-LABEL: name: dont_fold_negative_offset
    ; CHECK: liveins: $x0
    ; CHECK: %global:_(p0) = G_GLOBAL_VALUE @g
    ; CHECK: %offset:_(s64) = G_CONSTANT i64 -1
    ; CHECK: %ptr_add:_(p0) = G_PTR_ADD %global, %offset(s64)
    ; CHECK: $x0 = COPY %ptr_add(p0)
    ; CHECK: RET_ReallyLR implicit $x0
    %global:_(p0) = G_GLOBAL_VALUE @g
    %offset:_(s64) = G_CONSTANT i64 -1
    %ptr_add:_(p0) = G_PTR_ADD %global, %offset(s64)
    $x0 = COPY %ptr_add
    RET_ReallyLR implicit $x0

...
---
name:            dont_min_offset_less_than_curr_offset
alignment:       4
tracksRegLiveness: true
machineFunctionInfo: {}
body:             |
  bb.0:
    liveins: $x0

    ; Do not create smaller offsets. Ensures combine termination.

    ; CHECK-LABEL: name: dont_min_offset_less_than_curr_offset
    ; CHECK: liveins: $x0
    ; CHECK: %global:_(p0) = G_GLOBAL_VALUE @g + 3
    ; CHECK: %offset:_(s64) = G_CONSTANT i64 -1
    ; CHECK: %ptr_add:_(p0) = G_PTR_ADD %global, %offset(s64)
    ; CHECK: $x0 = COPY %ptr_add(p0)
    ; CHECK: RET_ReallyLR implicit $x0
    %global:_(p0) = G_GLOBAL_VALUE @g + 3
    %offset:_(s64) = G_CONSTANT i64 -1
    %ptr_add:_(p0) = G_PTR_ADD %global, %offset(s64)
    $x0 = COPY %ptr_add
    RET_ReallyLR implicit $x0

...
---
name:            dont_fold_max_offset
alignment:       4
tracksRegLiveness: true
machineFunctionInfo: {}
body:             |
  bb.0:
    liveins: $x0

    ; 1 << 21 is the largest offset expressible in all object formats.
    ; Don't fold it.

    ; CHECK-LABEL: name: dont_fold_max_offset
    ; CHECK: liveins: $x0
    ; CHECK: %global:_(p0) = G_GLOBAL_VALUE @g
    ; CHECK: %offset:_(s64) = G_CONSTANT i64 4292870144
    ; CHECK: %ptr_add:_(p0) = G_PTR_ADD %global, %offset(s64)
    ; CHECK: $x0 = COPY %ptr_add(p0)
    ; CHECK: RET_ReallyLR implicit $x0
    %global:_(p0) = G_GLOBAL_VALUE @g
    %offset:_(s64) = G_CONSTANT i64 4292870144 ; 1 << 21
    %ptr_add:_(p0) = G_PTR_ADD %global, %offset(s64)
    $x0 = COPY %ptr_add
    RET_ReallyLR implicit $x0

...
---
name:            dont_fold_offset_larger_than_type_alloc
alignment:       4
tracksRegLiveness: true
machineFunctionInfo: {}
body:             |
  bb.0:

    ; Type alloc size = 4, offset = 16. Don't fold.

    ; CHECK-LABEL: name: dont_fold_offset_larger_than_type_alloc
    ; CHECK: %global:_(p0) = G_GLOBAL_VALUE @g
    ; CHECK: %offset:_(s64) = G_CONSTANT i64 16
    ; CHECK: %ptr_add:_(p0) = G_PTR_ADD %global, %offset(s64)
    ; CHECK: $x0 = COPY %ptr_add(p0)
    ; CHECK: RET_ReallyLR implicit $x0
    %global:_(p0) = G_GLOBAL_VALUE @g
    %offset:_(s64) = G_CONSTANT i64 16
    %ptr_add:_(p0) = G_PTR_ADD %global, %offset(s64)
    $x0 = COPY %ptr_add(p0)
    RET_ReallyLR implicit $x0

...
---
name:            dont_fold_unsized_type
alignment:       4
tracksRegLiveness: true
machineFunctionInfo: {}
body:             |
  bb.0:
    ; Check that we don't touch unsized globals.

    ; CHECK-LABEL: name: dont_fold_unsized_type
    ; CHECK: %global:_(p0) = G_GLOBAL_VALUE @unsized
    ; CHECK: %offset:_(s64) = G_CONSTANT i64 16
    ; CHECK: %ptr_add:_(p0) = G_PTR_ADD %global, %offset(s64)
    ; CHECK: $x0 = COPY %ptr_add(p0)
    ; CHECK: RET_ReallyLR implicit $x0
    %global:_(p0) = G_GLOBAL_VALUE @unsized
    %offset:_(s64) = G_CONSTANT i64 16
    %ptr_add:_(p0) = G_PTR_ADD %global, %offset(s64)
    $x0 = COPY %ptr_add(p0)
    RET_ReallyLR implicit $x0