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; RUN: opt < %s -functionattrs -S | not grep {nocapture *%%q}
; RUN: opt < %s -functionattrs -S | grep {nocapture *%%p} | count 6
@g = global i32* null ; <i32**> [#uses=1]
define i32* @c1(i32* %q) {
ret i32* %q
}
define void @c2(i32* %q) {
store i32* %q, i32** @g
ret void
}
define void @c3(i32* %q) {
call void @c2(i32* %q)
ret void
}
define i1 @c4(i32* %q, i32 %bitno) {
%tmp = ptrtoint i32* %q to i32
%tmp2 = lshr i32 %tmp, %bitno
%bit = trunc i32 %tmp2 to i1
br i1 %bit, label %l1, label %l0
l0:
ret i1 0 ; escaping value not caught by def-use chaining.
l1:
ret i1 1 ; escaping value not caught by def-use chaining.
}
@lookup_table = global [2 x i1] [ i1 0, i1 1 ]
define i1 @c5(i32* %q, i32 %bitno) {
%tmp = ptrtoint i32* %q to i32
%tmp2 = lshr i32 %tmp, %bitno
%bit = and i32 %tmp2, 1
; subtle escape mechanism follows
%lookup = getelementptr [2 x i1]* @lookup_table, i32 0, i32 %bit
%val = load i1* %lookup
ret i1 %val
}
declare void @throw_if_bit_set(i8*, i8) readonly
define i1 @c6(i8* %q, i8 %bit) {
invoke void @throw_if_bit_set(i8* %q, i8 %bit)
to label %ret0 unwind label %ret1
ret0:
ret i1 0
ret1:
ret i1 1
}
define i1* @lookup_bit(i32* %q, i32 %bitno) readnone nounwind {
%tmp = ptrtoint i32* %q to i32
%tmp2 = lshr i32 %tmp, %bitno
%bit = and i32 %tmp2, 1
%lookup = getelementptr [2 x i1]* @lookup_table, i32 0, i32 %bit
ret i1* %lookup
}
define i1 @c7(i32* %q, i32 %bitno) {
%ptr = call i1* @lookup_bit(i32* %q, i32 %bitno)
%val = load i1* %ptr
ret i1 %val
}
define i32 @nc1(i32* %q, i32* %p, i1 %b) {
e:
br label %l
l:
%x = phi i32* [ %p, %e ]
%y = phi i32* [ %q, %e ]
%tmp = bitcast i32* %x to i32* ; <i32*> [#uses=2]
%tmp2 = select i1 %b, i32* %tmp, i32* %y
%val = load i32* %tmp2 ; <i32> [#uses=1]
store i32 0, i32* %tmp
store i32* %y, i32** @g
ret i32 %val
}
define void @nc2(i32* %p, i32* %q) {
%1 = call i32 @nc1(i32* %q, i32* %p, i1 0) ; <i32> [#uses=0]
ret void
}
define void @nc3(void ()* %p) {
call void %p()
ret void
}
declare void @external(i8*) readonly nounwind
define void @nc4(i8* %p) {
call void @external(i8* %p)
ret void
}
define void @nc5(void (i8*)* %f, i8* %p) {
call void %f(i8* %p) readonly nounwind
call void %f(i8* nocapture %p)
ret void
}
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