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| author | Richard Biener <rguenther@suse.de> | 2021-07-01 12:49:45 +0200 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2021-07-01 13:38:59 +0200 |
| commit | 0a77c07b9b3fe83679358c3ef57721e09e2ad5fb (patch) | |
| tree | 27e44924fdf36ccf4e2d4bd2f277440e76d08f71 /gcc | |
| parent | 09a7b00ac3075e3544978027f47b68fce54adabb (diff) | |
| download | gcc-0a77c07b9b3fe83679358c3ef57721e09e2ad5fb.zip gcc-0a77c07b9b3fe83679358c3ef57721e09e2ad5fb.tar.gz gcc-0a77c07b9b3fe83679358c3ef57721e09e2ad5fb.tar.bz2 | |
tree-optimization/101280 - revise interchange fix for PR101173
The following revises the original fix for PR101173 to correctly
check for a reversed dependence rather than disallowing a zero
distance. It also adds a check from TSVC which asks for this
kind of interchange (but with a valid dependence).
2021-07-01 Richard Biener <rguenther@suse.de>
PR tree-optimization/101280
PR tree-optimization/101173
* gimple-loop-interchange.cc
(tree_loop_interchange::valid_data_dependences): Revert
previous change and instead correctly handle DDR_REVERSED_P
dependence.
* gcc.dg/tree-ssa/loop-interchange-16.c: New testcase.
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/gimple-loop-interchange.cc | 7 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/tree-ssa/loop-interchange-16.c | 22 |
2 files changed, 27 insertions, 2 deletions
diff --git a/gcc/gimple-loop-interchange.cc b/gcc/gimple-loop-interchange.cc index 43045c54..43ef112 100644 --- a/gcc/gimple-loop-interchange.cc +++ b/gcc/gimple-loop-interchange.cc @@ -1043,8 +1043,11 @@ tree_loop_interchange::valid_data_dependences (unsigned i_idx, unsigned o_idx, continue; /* Be conservative, skip case if either direction at i_idx/o_idx - levels is not '=' (for the inner loop) or '<'. */ - if (dist_vect[i_idx] < 0 || dist_vect[o_idx] <= 0) + levels is not '=' or '<'. */ + if (dist_vect[i_idx] < 0 + || (DDR_REVERSED_P (ddr) && dist_vect[i_idx] > 0) + || dist_vect[o_idx] < 0 + || (DDR_REVERSED_P (ddr) && dist_vect[o_idx] > 0)) return false; } } diff --git a/gcc/testsuite/gcc.dg/tree-ssa/loop-interchange-16.c b/gcc/testsuite/gcc.dg/tree-ssa/loop-interchange-16.c new file mode 100644 index 0000000..781555e --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/loop-interchange-16.c @@ -0,0 +1,22 @@ +/* PR/101280 */ +/* { dg-do compile } */ +/* { dg-options "-O3 -fdump-tree-linterchange-details" } */ + +void dummy (double *, double *); +#define LEN_2D 32 +double aa[LEN_2D][LEN_2D], bb[LEN_2D][LEN_2D]; +double s231(int iterations) +{ +// loop interchange +// loop with data dependency + for (int nl = 0; nl < 100*(iterations/LEN_2D); nl++) { + for (int i = 0; i < LEN_2D; ++i) { + for (int j = 1; j < LEN_2D; j++) { + aa[j][i] = aa[j - 1][i] + bb[j][i]; + } + } + dummy(aa[0],bb[0]); + } +} + +/* { dg-final { scan-tree-dump "loops interchanged" "linterchange" } } */ |