[LLVMdev] How to avoid this transformation

[Chris Lattner]

On Mon, 25 Apr 2005, Ricardo wrote:
> I am trying to compile a program to be used for Pool Allocation. The program tries to allocate
> certain number of nodes inside a function that is called by main. The problem is that llvm-gcc
> insists in "optimize" the function so that certain number of nodes are created in main and the
> rest are created inside the original function. In this case the function is called with a minor
> number of nodes two times. My question is: how to supress this transformation? I am compiling
> using this line:
>
> llvm-gcc -o tree tree.c
>
> So that I am not enabling any optimization and I am not running either DSA or PoolAlloc. I use the
> unoptimized .bc file generated and convert it either to .c or .ll and both formats exhibit this
> behavior

llvm-gcc is strange in that it runs optimizations even when not asked to. 
Try this:

llvm-gcc -o tree tree.c -Wa,-disable-inlining -Wl,-disable-inlining

-Chris



> =======================
> struct bintree
> {
> 	int data;
> 	struct bintree *Left;
> 	struct bintree *Right;
> };
>
> void inorder_traversal(struct bintree *node)
> {
> 	if (node->Left != 0)  inorder_traversal( node->Left );
> 	printf("%d\t", node->data);
> 	if (node->Right != 0) inorder_traversal( node->Right );
> }
>
> struct bintree *make_tree(int level)
> {
> 	struct bintree  *New = malloc ( sizeof ( struct bintree ) );
> 	New->Left  = level ? make_tree (level-1) : 0;
> 	New->data = level;
> 	New->Right = level ? make_tree (level-1) : 0;
> 	return New;
> }
>
> int main()
> {
> 	struct bintree *root;
> 	root = make_tree(1000);
> 	printf("\n");
> 	inorder_traversal( root );
> 	printf("\n");
> 	return 0;
> }
> =======================
>

-Chris

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