llvm/test/Transforms/Sink/invariant-load.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -passes=sink -S < %s | FileCheck %s

; Loads marked invariant can be sunk across critical edges.

define <4 x float> @invariant_load(ptr %in, i32 %s) {
; CHECK-LABEL: @invariant_load(
; CHECK-NEXT:  main_body:
; CHECK-NEXT:    [[C:%.*]] = icmp eq i32 [[S:%.*]], 0
; CHECK-NEXT:    br i1 [[C]], label [[BLOCK:%.*]], label [[END:%.*]]
; CHECK:       block:
; CHECK-NEXT:    [[Z:%.*]] = add i32 [[S]], 1
; CHECK-NEXT:    br label [[END]]
; CHECK:       end:
; CHECK-NEXT:    [[V:%.*]] = load <4 x float>, ptr [[IN:%.*]], align 16, !invariant.load [[META0:![0-9]+]]
; CHECK-NEXT:    ret <4 x float> [[V]]
;
main_body:
  %v = load <4 x float>, ptr %in, !invariant.load !0
  %c = icmp eq i32 %s, 0
  br i1 %c, label %block, label %end
block:
  %z = add i32 %s, 1
  br label %end
end:
  ret <4 x float> %v
}

; Loads that aren't marked invariant but used in one branch
; can be sunk to that branch.

define void @invariant_load_use_in_br(ptr %p, i1 %cond) {
; CHECK-LABEL: @invariant_load_use_in_br(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    br i1 [[COND:%.*]], label [[TRUE_BR:%.*]], label [[FALSE_BR:%.*]]
; CHECK:       true.br:
; CHECK-NEXT:    call void @fn()
; CHECK-NEXT:    br label [[EXIT:%.*]]
; CHECK:       false.br:
; CHECK-NEXT:    [[VAL:%.*]] = load i32, ptr [[P:%.*]], align 4
; CHECK-NEXT:    call void @fn(i32 [[VAL]])
; CHECK-NEXT:    br label [[EXIT]]
; CHECK:       exit:
; CHECK-NEXT:    ret void
;
entry:
  %val = load i32, ptr %p
  br i1 %cond, label %true.br, label %false.br
true.br:
  call void @fn()
  br label %exit
false.br:
  call void @fn(i32 %val)
  br label %exit
exit:
  ret void
}

; TODO: Invariant loads marked with metadata can be sunk past calls.

define void @invariant_load_metadata_call(ptr %p, i1 %cond) {
; CHECK-LABEL: @invariant_load_metadata_call(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[VAL:%.*]] = load i32, ptr [[P:%.*]], align 4, !invariant.load [[META0]]
; CHECK-NEXT:    call void @fn()
; CHECK-NEXT:    br i1 [[COND:%.*]], label [[TRUE_BR:%.*]], label [[FALSE_BR:%.*]]
; CHECK:       true.br:
; CHECK-NEXT:    call void @fn()
; CHECK-NEXT:    br label [[EXIT:%.*]]
; CHECK:       false.br:
; CHECK-NEXT:    call void @fn(i32 [[VAL]])
; CHECK-NEXT:    br label [[EXIT]]
; CHECK:       exit:
; CHECK-NEXT:    ret void
;
entry:
  %val = load i32, ptr %p, !invariant.load !0
  call void @fn()
  br i1 %cond, label %true.br, label %false.br
true.br:
  call void @fn()
  br label %exit
false.br:
  call void @fn(i32 %val)
  br label %exit
exit:
  ret void
}

declare void @fn()

!0 = !{}