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| ; ModuleID = 'PR1657.bc'
; Do not promote getelementptr because it may exposes load from a null pointer
; and store from a null pointer which are covered by
; icmp eq %struct.decision* null, null condition.
; RUN: opt < %s -licm -S | not grep promoted
%struct.decision = type { i8, %struct.decision* }
define i32 @main() {
entry:
br label %blah.i
blah.i: ; preds = %cond_true.i, %entry
%tmp3.i = icmp eq %struct.decision* null, null ; <i1> [#uses=1]
br i1 %tmp3.i, label %clear_modes.exit, label %cond_true.i
cond_true.i: ; preds = %blah.i
%tmp1.i = getelementptr %struct.decision, %struct.decision* null, i32 0, i32 0 ; <i8*> [#uses=1]
store i8 0, i8* %tmp1.i
br label %blah.i
clear_modes.exit: ; preds = %blah.i
call void @exit( i32 0 )
unreachable
}
define i32 @f(i8* %ptr) {
entry:
br label %loop.head
loop.head: ; preds = %cond.true, %entry
%x = phi i8* [ %ptr, %entry ], [ %ptr.i, %cond.true ] ; <i8*> [#uses=1]
%tmp3.i = icmp ne i8* %ptr, %x ; <i1> [#uses=1]
br i1 %tmp3.i, label %cond.true, label %exit
cond.true: ; preds = %loop.head
%ptr.i = getelementptr i8, i8* %ptr, i32 0 ; <i8*> [#uses=2]
store i8 0, i8* %ptr.i
br label %loop.head
exit: ; preds = %loop.head
ret i32 0
}
define i32 @f2(i8* %p, i8* %q) {
entry:
br label %loop.head
loop.head: ; preds = %cond.true, %entry
%tmp3.i = icmp eq i8* null, %q ; <i1> [#uses=1]
br i1 %tmp3.i, label %exit, label %cond.true
cond.true: ; preds = %loop.head
%ptr.i = getelementptr i8, i8* %p, i32 0 ; <i8*> [#uses=2]
store i8 0, i8* %ptr.i
br label %loop.head
exit: ; preds = %loop.head
ret i32 0
}
declare void @exit(i32)
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