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; RUN: llc < %s
; REQUIRES: default_triple
declare i8* @llvm_gc_allocate(i32)
declare void @llvm_gc_initialize(i32)
declare void @llvm.gcroot(i8**, i8*)
declare void @llvm.gcwrite(i8*, i8*, i8**)
define i32 @main() gc "shadow-stack" {
entry:
%A = alloca i8*
%B = alloca i8**
call void @llvm_gc_initialize(i32 1048576) ; Start with 1MB heap
;; void *A;
call void @llvm.gcroot(i8** %A, i8* null)
;; A = gcalloc(10);
%Aptr = call i8* @llvm_gc_allocate(i32 10)
store i8* %Aptr, i8** %A
;; void **B;
%tmp.1 = bitcast i8*** %B to i8**
call void @llvm.gcroot(i8** %tmp.1, i8* null)
;; B = gcalloc(4);
%B.upgrd.1 = call i8* @llvm_gc_allocate(i32 8)
%tmp.2 = bitcast i8* %B.upgrd.1 to i8**
store i8** %tmp.2, i8*** %B
;; *B = A;
%B.1 = load i8**, i8*** %B
%A.1 = load i8*, i8** %A
call void @llvm.gcwrite(i8* %A.1, i8* %B.upgrd.1, i8** %B.1)
br label %AllocLoop
AllocLoop:
%i = phi i32 [ 0, %entry ], [ %indvar.next, %AllocLoop ]
;; Allocated mem: allocated memory is immediately dead.
call i8* @llvm_gc_allocate(i32 100)
%indvar.next = add i32 %i, 1
%exitcond = icmp eq i32 %indvar.next, 10000000
br i1 %exitcond, label %Exit, label %AllocLoop
Exit:
ret i32 0
}
declare void @__main()
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