2016-01-05 08:48:16 +08:00
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; RUN: llc -o - %s | FileCheck %s
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; This tests for the problem originally reported in http://llvm.org/PR25951
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target triple = "i686-unknown-linux-gnu"
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@b = common global i8 0, align 1
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@c = common global i32 0, align 4
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@a = common global i8 0, align 1
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@d = common global i8 0, align 1
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@.str = private unnamed_addr constant [4 x i8] c"%d\0A\00", align 1
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; CHECK-LABEL: func:
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2016-10-14 04:23:25 +08:00
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; This tests whether eax is properly saved/restored around the lahf/sahf
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; instruction sequences.
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2016-01-05 08:48:16 +08:00
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define i32 @func() {
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entry:
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%bval = load i8, i8* @b
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%inc = add i8 %bval, 1
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2016-10-14 04:23:25 +08:00
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store i8 %inc, i8* @b
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%cval = load i32, i32* @c
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2016-01-05 08:48:16 +08:00
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%inc1 = add nsw i32 %cval, 1
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2016-10-14 04:23:25 +08:00
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store i32 %inc1, i32* @c
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%aval = load i8, i8* @a
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2016-01-05 08:48:16 +08:00
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%inc2 = add i8 %aval, 1
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2016-10-14 04:23:25 +08:00
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store i8 %inc2, i8* @a
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2016-01-05 08:48:16 +08:00
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; Copy flags produced by the incb of %inc1 to a register, need to save+restore
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; eax around it. The flags will be reused by %tobool.
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; CHECK: pushl %eax
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; CHECK: seto %al
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; CHECK: lahf
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; CHECK: movl %eax, [[REG:%[a-z]+]]
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; CHECK: popl %eax
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%cmp = icmp eq i8 %aval, %bval
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%conv5 = zext i1 %cmp to i8
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store i8 %conv5, i8* @d
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%tobool = icmp eq i32 %inc1, 0
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; We restore flags with an 'addb, sahf' sequence, need to save+restore eax
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; around it.
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; CHECK: pushl %eax
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; CHECK: movl [[REG]], %eax
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; CHECK: addb $127, %al
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; CHECK: sahf
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; CHECK: popl %eax
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br i1 %tobool, label %if.end, label %if.then
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if.then:
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%conv6 = sext i8 %inc to i32
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%call = tail call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), i32 %conv6)
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br label %if.end
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if.end:
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ret i32 0
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}
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declare i32 @printf(i8* nocapture readonly, ...)
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