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; RUN: opt -S -o - -basicaa -domtree -gvn %s | FileCheck %s
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
%struct.S1 = type { i32, i32 }
@a2 = common global i32* null, align 8
@a = common global i32* null, align 8
@s1 = common global %struct.S1 zeroinitializer, align 8
; Check that GVN doesn't determine %2 is partially redundant.
; CHECK-LABEL: define i32 @volatile_load
; CHECK: for.body:
; CHECK: %2 = load i32, i32*
; CHECK: %3 = load volatile i32, i32*
; CHECK: for.cond.for.end_crit_edge:
define i32 @volatile_load(i32 %n) {
entry:
%cmp6 = icmp sgt i32 %n, 0
br i1 %cmp6, label %for.body.lr.ph, label %for.end
for.body.lr.ph:
%0 = load i32*, i32** @a2, align 8, !tbaa !1
%1 = load i32*, i32** @a, align 8, !tbaa !1
br label %for.body
for.body:
%indvars.iv = phi i64 [ 0, %for.body.lr.ph ], [ %indvars.iv.next, %for.body ]
%s.09 = phi i32 [ 0, %for.body.lr.ph ], [ %add, %for.body ]
%p.08 = phi i32* [ %0, %for.body.lr.ph ], [ %incdec.ptr, %for.body ]
%2 = load i32, i32* %p.08, align 4, !tbaa !5
%arrayidx = getelementptr inbounds i32, i32* %1, i64 %indvars.iv
store i32 %2, i32* %arrayidx, align 4, !tbaa !5
%3 = load volatile i32, i32* %p.08, align 4, !tbaa !5
%add = add nsw i32 %3, %s.09
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%incdec.ptr = getelementptr inbounds i32, i32* %p.08, i64 1
%lftr.wideiv = trunc i64 %indvars.iv.next to i32
%exitcond = icmp ne i32 %lftr.wideiv, %n
br i1 %exitcond, label %for.body, label %for.cond.for.end_crit_edge
for.cond.for.end_crit_edge:
%add.lcssa = phi i32 [ %add, %for.body ]
br label %for.end
for.end:
%s.0.lcssa = phi i32 [ %add.lcssa, %for.cond.for.end_crit_edge ], [ 0, %entry ]
ret i32 %s.0.lcssa
}
; %1 is partially redundant if %0 can be widened to a 64-bit load.
; CHECK-LABEL: define i32 @overaligned_load
; CHECK: if.end:
; CHECK-NOT: %1 = load i32, i32*
define i32 @overaligned_load(i32 %a, i32* nocapture %b) {
entry:
%cmp = icmp sgt i32 %a, 0
br i1 %cmp, label %if.then, label %if.else
if.then:
%0 = load i32, i32* getelementptr inbounds (%struct.S1, %struct.S1* @s1, i64 0, i32 0), align 8, !tbaa !5
br label %if.end
if.else:
%arrayidx = getelementptr inbounds i32, i32* %b, i64 2
store i32 10, i32* %arrayidx, align 4, !tbaa !5
br label %if.end
if.end:
%i.0 = phi i32 [ %0, %if.then ], [ 0, %if.else ]
%p.0 = phi i32* [ getelementptr inbounds (%struct.S1, %struct.S1* @s1, i64 0, i32 0), %if.then ], [ %b, %if.else ]
%add.ptr = getelementptr inbounds i32, i32* %p.0, i64 1
%1 = load i32, i32* %add.ptr, align 4, !tbaa !5
%add1 = add nsw i32 %1, %i.0
ret i32 %add1
}
!1 = !{!2, !2, i64 0}
!2 = !{!"any pointer", !3, i64 0}
!3 = !{!"omnipotent char", !4, i64 0}
!4 = !{!"Simple C/C++ TBAA"}
!5 = !{!6, !6, i64 0}
!6 = !{!"int", !3, i64 0}
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