forked from OSchip/llvm-project
59 lines
1.4 KiB
LLVM
59 lines
1.4 KiB
LLVM
; RUN: opt < %s -loop-unswitch -verify-loop-info -S < %s 2>&1 | FileCheck %s
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; There are 1 case and 1 default case in the switch. after we unswitch, we know the
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; %a is definitely not 0 in one of the unswitched loop, make sure we take advantage
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; of that and simplify the branches in the loop.
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;
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; CHECK: define void @simplify_with_nonvalness(
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; This is the loop in which we know %a is definitely 0.
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; CHECK: sw.bb.us:
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; CHECK: br i1 true, label %if.then.us, label %if.end.us
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; This is the loop in which we do not know what %a is but we know %a is definitely NOT 0.
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; Make sure we use that information to simplify.
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; The icmp eq i32 %a, 0 in one of the unswitched loop is simplified to false.
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; CHECK: sw.bb.split:
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; CHECK: br i1 false, label %if.then, label %if.end
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define void @simplify_with_nonvalness(i32 %a) #0 {
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entry:
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br label %for.cond
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for.cond:
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%i.0 = phi i32 [ 0, %entry ], [ %inc, %for.inc ]
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%cmp = icmp slt i32 %i.0, 1024
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br i1 %cmp, label %for.body, label %for.end
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for.body:
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switch i32 %a, label %sw.default [
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i32 0, label %sw.bb
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]
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sw.bb:
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%cmp1 = icmp eq i32 %a, 0
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br i1 %cmp1, label %if.then, label %if.end
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if.then:
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call void (...) @bar()
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br label %if.end
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if.end:
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br label %sw.epilog
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sw.default:
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br label %sw.epilog
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sw.epilog:
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br label %for.inc
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for.inc:
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%inc = add nsw i32 %i.0, 1
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br label %for.cond
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for.end:
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ret void
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}
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declare void @bar(...)
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