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; RUN: opt -S -jump-threading < %s | FileCheck %s
declare i8* @escape()
declare void @llvm.assume(i1)
define i1 @test1(i1 %cond) {
entry:
br i1 %cond, label %taken, label %not_taken
; CHECK-LABEL: @test1
; CHECK: br i1 %cond, label %no, label %yes
; CHECK: ret i1 true
taken:
%res1 = call i8* @escape()
%a = icmp eq i8* %res1, null
tail call void @llvm.assume(i1 %a)
br label %done
not_taken:
%res2 = call i8* @escape()
%b = icmp ne i8* %res2, null
tail call void @llvm.assume(i1 %b)
br label %done
; An assume that can be used to simplify this comparison dominates each
; predecessor branch (although no assume dominates the cmp itself). Make sure
; this still can be simplified.
done:
%res = phi i8* [ %res1, %taken ], [ %res2, %not_taken ]
%cnd = icmp ne i8* %res, null
br i1 %cnd, label %yes, label %no
yes:
ret i1 true
no:
ret i1 false
}
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