| /* PR rtl-optimization/28982. Function foo() does the equivalent of: |
| |
| float tmp_results[NVARS]; |
| for (int i = 0; i < NVARS; i++) |
| { |
| int inc = incs[i]; |
| float *ptr = ptrs[i], result = 0; |
| for (int j = 0; j < n; j++) |
| result += *ptr, ptr += inc; |
| tmp_results[i] = result; |
| } |
| memcpy (results, tmp_results, sizeof (results)); |
| |
| but without the outermost loop. The idea is to create high register |
| pressure and ensure that some INC and PTR variables are spilled. |
| |
| On ARM targets, sequences like "result += *ptr, ptr += inc" can |
| usually be implemented using (mem (post_modify ...)), and we do |
| indeed create such MEMs before reload for this testcase. However, |
| (post_modify ...) is not a valid address for coprocessor loads, so |
| for -mfloat-abi=softfp, reload reloads the POST_MODIFY into a base |
| register. GCC did not deal correctly with cases where the base and |
| index of the POST_MODIFY are themselves reloaded. */ |
| #define NITER 4 |
| #define NVARS 20 |
| #define MULTI(X) \ |
| X( 0), X( 1), X( 2), X( 3), X( 4), X( 5), X( 6), X( 7), X( 8), X( 9), \ |
| X(10), X(11), X(12), X(13), X(14), X(15), X(16), X(17), X(18), X(19) |
| |
| #define DECLAREI(INDEX) inc##INDEX = incs[INDEX] |
| #define DECLAREF(INDEX) *ptr##INDEX = ptrs[INDEX], result##INDEX = 0 |
| #define LOOP(INDEX) result##INDEX += *ptr##INDEX, ptr##INDEX += inc##INDEX |
| #define COPYOUT(INDEX) results[INDEX] = result##INDEX |
| |
| float *ptrs[NVARS]; |
| float results[NVARS]; |
| int incs[NVARS]; |
| |
| void __attribute__((noinline)) |
| foo (int n) |
| { |
| int MULTI (DECLAREI); |
| float MULTI (DECLAREF); |
| while (n--) |
| MULTI (LOOP); |
| MULTI (COPYOUT); |
| } |
| |
| float input[NITER * NVARS]; |
| |
| int |
| main (void) |
| { |
| int i; |
| |
| for (i = 0; i < NVARS; i++) |
| ptrs[i] = input + i, incs[i] = i; |
| for (i = 0; i < NITER * NVARS; i++) |
| input[i] = i; |
| foo (NITER); |
| for (i = 0; i < NVARS; i++) |
| if (results[i] != i * NITER * (NITER + 1) / 2) |
| return 1; |
| return 0; |
| } |