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