phi-cycle.ll
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; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
%struct.small = type { i8 }
@.str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
; Address-of a structure taken in a function with a loop where
; the alloca is an incoming value to a PHI node and a use of that PHI
; node is also an incoming value.
; Verify that the address-of analysis does not get stuck in infinite
; recursion when chasing the alloca through the PHI nodes.
; Requires protector.
define i32 @foo(i32 %arg) nounwind uwtable safestack {
bb:
; CHECK: __safestack_unsafe_stack_ptr
%tmp = alloca %struct.small*, align 8
%tmp1 = call i32 (...) @dummy(%struct.small** %tmp) nounwind
%tmp2 = load %struct.small*, %struct.small** %tmp, align 8
%tmp3 = ptrtoint %struct.small* %tmp2 to i64
%tmp4 = trunc i64 %tmp3 to i32
%tmp5 = icmp sgt i32 %tmp4, 0
br i1 %tmp5, label %bb6, label %bb21
bb6: ; preds = %bb17, %bb
%tmp7 = phi %struct.small* [ %tmp19, %bb17 ], [ %tmp2, %bb ]
%tmp8 = phi i64 [ %tmp20, %bb17 ], [ 1, %bb ]
%tmp9 = phi i32 [ %tmp14, %bb17 ], [ %tmp1, %bb ]
%tmp10 = getelementptr inbounds %struct.small, %struct.small* %tmp7, i64 0, i32 0
%tmp11 = load i8, i8* %tmp10, align 1
%tmp12 = icmp eq i8 %tmp11, 1
%tmp13 = add nsw i32 %tmp9, 8
%tmp14 = select i1 %tmp12, i32 %tmp13, i32 %tmp9
%tmp15 = trunc i64 %tmp8 to i32
%tmp16 = icmp eq i32 %tmp15, %tmp4
br i1 %tmp16, label %bb21, label %bb17
bb17: ; preds = %bb6
%tmp18 = getelementptr inbounds %struct.small*, %struct.small** %tmp, i64 %tmp8
%tmp19 = load %struct.small*, %struct.small** %tmp18, align 8
%tmp20 = add i64 %tmp8, 1
br label %bb6
bb21: ; preds = %bb6, %bb
%tmp22 = phi i32 [ %tmp1, %bb ], [ %tmp14, %bb6 ]
%tmp23 = call i32 (...) @dummy(i32 %tmp22) nounwind
ret i32 undef
}
declare i32 @dummy(...)