1//===- subzero/crosstest/test_stacksave.c - Implementation for tests ------===//
2//
3//                        The Subzero Code Generator
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This aims to test that C99's VLAs (which use stacksave/stackrestore
11// intrinsics) work fine.
12//
13//===----------------------------------------------------------------------===//
14
15#include <stdint.h>
16
17#include "test_stacksave.h"
18DECLARE_TESTS()
19
20/* NOTE: This has 0 stacksaves, because the vla isn't in a loop,
21 * so the vla can just be freed by the epilogue.
22 */
23uint32_t test_basic_vla(uint32_t size, uint32_t start, uint32_t inc) {
24  uint32_t vla[size];
25  uint32_t mid = start + ((size - start) / 2);
26  for (uint32_t i = start; i < size; ++i) {
27    vla[i] = i + inc;
28  }
29  return (vla[start] << 2) + (vla[mid] << 1) + vla[size - 1];
30}
31
32static uint32_t __attribute__((noinline)) foo(uint32_t x) { return x * x; }
33
34/* NOTE: This has 1 stacksave, because the vla is in a loop and should
35 * be freed before the next iteration.
36 */
37uint32_t test_vla_in_loop(uint32_t size, uint32_t start, uint32_t inc) {
38  uint32_t sum = 0;
39  for (uint32_t i = start; i < size; ++i) {
40    uint32_t size1 = size - i;
41    uint32_t vla[size1];
42    for (uint32_t j = 0; j < size1; ++j) {
43      /* Adjust stack again with a function call. */
44      vla[j] = foo(start * j + inc);
45    }
46    for (uint32_t j = 0; j < size1; ++j) {
47      sum += vla[j];
48    }
49  }
50  return sum;
51}
52
53uint32_t test_two_vlas_in_loops(uint32_t size, uint32_t start, uint32_t inc) {
54  uint32_t sum = 0;
55  for (uint32_t i = start; i < size; ++i) {
56    uint32_t size1 = size - i;
57    uint32_t vla1[size1];
58    for (uint32_t j = 0; j < size1; ++j) {
59      uint32_t size2 = size - j;
60      uint32_t start2 = 0;
61      uint32_t mid2 = size2 / 2;
62      uint32_t vla2[size2];
63      for (uint32_t k = start2; k < size2; ++k) {
64        /* Adjust stack again with a function call. */
65        vla2[k] = foo(start * k + inc);
66      }
67      vla1[j] = (vla2[start2] << 2) + (vla2[mid2] << 1) + vla2[size2 - 1];
68    }
69    for (uint32_t j = 0; j < size1; ++j) {
70      sum += vla1[j];
71    }
72  }
73  return sum;
74}
75