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<p class="MsoNormal">In the following code, I <b><u>know</u></b> that the alloca, load and store are actually unnecessary (it is safe to pass @foo directly to the function boo). Are there any attributes one can set on function `boo` AND/OR its argument pointer
AND/OR on the call so that the three instructions can be eliminated and the argument of call @boo be replaced with @foo (is there a transform that can actually do this today?)
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">; ModuleID = '<stdin>'<o:p></o:p></p>
<p class="MsoNormal">source_filename = "test.c"<o:p></o:p></p>
<p class="MsoNormal">target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"<o:p></o:p></p>
<p class="MsoNormal">target triple = "x86_64-unknown-linux-gnu"<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">@foo = common dso_local local_unnamed_addr global i32 0, align 4<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">; Function Attrs: noinline nounwind uwtable<o:p></o:p></p>
<p class="MsoNormal">define dso_local void @f() local_unnamed_addr #0 {<o:p></o:p></p>
<p class="MsoNormal"> <span style="background:yellow;mso-highlight:yellow">%A = alloca i32, align 4<o:p></o:p></span></p>
<p class="MsoNormal"><span style="background:yellow;mso-highlight:yellow"> %L = load i32, i32* @foo, align 4<o:p></o:p></span></p>
<p class="MsoNormal"><span style="background:yellow;mso-highlight:yellow"> store i32 %L, i32* %A, align 4</span><o:p></o:p></p>
<p class="MsoNormal"> call void @boo(i32* nonnull %A) #2<o:p></o:p></p>
<p class="MsoNormal"> ret void<o:p></o:p></p>
<p class="MsoNormal">}<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">declare dso_local void @boo(i32* readonly noalias nocapture) local_unnamed_addr argmemonly #1<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">attributes #0 = { noinline nounwind uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "frame-pointer"="all" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-infs-fp-math"="false" "no-jump-tables"="false"
"no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }<o:p></o:p></p>
<p class="MsoNormal">attributes #1 = { "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "frame-pointer"="all" "less-precise-fpmad"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false"
"stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }<o:p></o:p></p>
<p class="MsoNormal">attributes #2 = { nounwind }<o:p></o:p></p>
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