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; RUN: opt -basicaa -gvn -S < %s | FileCheck %s
target datalayout = "e-p:64:64:64"
; GVN should ignore the store to p[1] to see that the load from p[0] is
; fully redundant.
; CHECK-LABEL: @yes(
; CHECK: if.then:
; CHECK-NEXT: store i32 0, i32* %q
; CHECK-NEXT: ret void
define void @yes(i1 %c, i32* %p, i32* %q) nounwind {
entry:
store i32 0, i32* %p
%p1 = getelementptr inbounds i32* %p, i64 1
store i32 1, i32* %p1
br i1 %c, label %if.else, label %if.then
if.then:
%t = load i32* %p
store i32 %t, i32* %q
ret void
if.else:
ret void
}
; GVN should ignore the store to p[1] to see that the first load from p[0] is
; fully redundant. However, the second load is larger, so it's not a simple
; redundancy.
; CHECK-LABEL: @watch_out_for_size_change(
; CHECK: if.then:
; CHECK-NEXT: store i32 0, i32* %q
; CHECK-NEXT: ret void
; CHECK: if.else:
; CHECK: load i64* %pc
; CHECK: store i64
define void @watch_out_for_size_change(i1 %c, i32* %p, i32* %q) nounwind {
entry:
store i32 0, i32* %p
%p1 = getelementptr inbounds i32* %p, i64 1
store i32 1, i32* %p1
br i1 %c, label %if.else, label %if.then
if.then:
%t = load i32* %p
store i32 %t, i32* %q
ret void
if.else:
%pc = bitcast i32* %p to i64*
%qc = bitcast i32* %q to i64*
%t64 = load i64* %pc
store i64 %t64, i64* %qc
ret void
}
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