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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -passes=simplifycfg -S | FileCheck %s
declare void @bar()
declare i1 @uniform_result(i1 %c)
define void @dont_merge_cbranches1(i32 %V) {
; CHECK-LABEL: @dont_merge_cbranches1(
; CHECK-NEXT: [[DIVERGENT_COND:%.*]] = icmp ne i32 [[V:%.*]], 0
; CHECK-NEXT: [[UNIFORM_COND:%.*]] = call i1 @uniform_result(i1 [[DIVERGENT_COND]])
; CHECK-NEXT: br i1 [[UNIFORM_COND]], label [[BB2:%.*]], label [[EXIT:%.*]], !prof [[PROF0:![0-9]+]]
; CHECK: bb2:
; CHECK-NEXT: br i1 [[DIVERGENT_COND]], label [[BB3:%.*]], label [[EXIT]]
; CHECK: bb3:
; CHECK-NEXT: call void @bar()
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret void
;
%divergent_cond = icmp ne i32 %V, 0
%uniform_cond = call i1 @uniform_result(i1 %divergent_cond)
br i1 %uniform_cond, label %bb2, label %exit, !prof !0
bb2:
br i1 %divergent_cond, label %bb3, label %exit
bb3:
call void @bar( )
br label %exit
exit:
ret void
}
define void @dont_merge_cbranches2(i32 %V) {
; CHECK-LABEL: @dont_merge_cbranches2(
; CHECK-NEXT: [[DIVERGENT_COND:%.*]] = icmp ne i32 [[V:%.*]], 0
; CHECK-NEXT: [[UNIFORM_COND:%.*]] = call i1 @uniform_result(i1 [[DIVERGENT_COND]])
; CHECK-NEXT: br i1 [[UNIFORM_COND]], label [[EXIT:%.*]], label [[BB2:%.*]], !prof [[PROF1:![0-9]+]]
; CHECK: bb2:
; CHECK-NEXT: br i1 [[DIVERGENT_COND]], label [[BB3:%.*]], label [[EXIT]]
; CHECK: bb3:
; CHECK-NEXT: call void @bar()
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret void
;
%divergent_cond = icmp ne i32 %V, 0
%uniform_cond = call i1 @uniform_result(i1 %divergent_cond)
br i1 %uniform_cond, label %exit, label %bb2, !prof !1
bb2:
br i1 %divergent_cond, label %bb3, label %exit
bb3:
call void @bar( )
br label %exit
exit:
ret void
}
define void @merge_cbranches(i32 %V) {
; CHECK-LABEL: @merge_cbranches(
; CHECK-NEXT: [[DIVERGENT_COND:%.*]] = icmp ne i32 [[V:%.*]], 0
; CHECK-NEXT: [[UNIFORM_COND:%.*]] = call i1 @uniform_result(i1 [[DIVERGENT_COND]])
; CHECK-NEXT: [[DIVERGENT_COND_NOT:%.*]] = xor i1 [[DIVERGENT_COND]], true
; CHECK-NEXT: [[BRMERGE:%.*]] = select i1 [[UNIFORM_COND]], i1 true, i1 [[DIVERGENT_COND_NOT]]
; CHECK-NEXT: br i1 [[BRMERGE]], label [[EXIT:%.*]], label [[BB3:%.*]], !prof [[PROF2:![0-9]+]]
; CHECK: bb3:
; CHECK-NEXT: call void @bar()
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret void
;
%divergent_cond = icmp ne i32 %V, 0
%uniform_cond = call i1 @uniform_result(i1 %divergent_cond)
br i1 %uniform_cond, label %exit, label %bb2, !prof !2
bb2:
br i1 %divergent_cond, label %bb3, label %exit
bb3:
call void @bar( )
br label %exit
exit:
ret void
}
define void @uint32_overflow_test(i1 %arg, i1 %arg1) {
; CHECK-LABEL: @uint32_overflow_test(
; CHECK-NEXT: bb:
; CHECK-NEXT: [[BRMERGE:%.*]] = select i1 [[ARG:%.*]], i1 true, i1 [[ARG1:%.*]]
; CHECK-NEXT: ret void
;
bb:
br i1 %arg, label %bb4, label %bb2, !prof !3
bb2:
br i1 %arg1, label %bb4, label %bb3
bb3:
br label %bb4
bb4:
ret void
}
!0 = !{!"branch_weights", i32 1, i32 1000}
!1 = !{!"branch_weights", i32 1000, i32 1}
!2 = !{!"branch_weights", i32 3, i32 2}
!3 = !{!"branch_weights", i32 -258677585, i32 -1212131848}
|
