Mercurial > hg > CbC > CbC_gcc
diff gcc/testsuite/gcc.dg/loop-versioning-6.c @ 145:1830386684a0
gcc-9.2.0
author | anatofuz |
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date | Thu, 13 Feb 2020 11:34:05 +0900 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/gcc/testsuite/gcc.dg/loop-versioning-6.c Thu Feb 13 11:34:05 2020 +0900 @@ -0,0 +1,31 @@ +/* { dg-options "-O3 -fdump-tree-lversion-details" } */ + +/* The read from y in f1 will be hoisted to the outer loop. In general + it's not worth versioning outer loops when the inner loops don't also + benefit. + + This test is meant to be a slight counterexample, since versioning + does lead to cheaper outer-loop vectorization. However, the benefit + isn't enough to justify the cost. */ + +void +f1 (double *restrict x, double *restrict y, int step, int n) +{ + for (int i = 0; i < n; ++i) + for (int j = 0; j < n; ++j) + x[i + j] = y[i * step]; +} + +/* A similar example in which the read can't be hoisted, but could + for example be handled by vectorizer alias checks. */ + +void +f2 (double *x, double *y, int step, int n) +{ + for (int i = 0; i < n; ++i) + for (int j = 0; j < n; ++j) + x[i + j] = y[i * step]; +} + +/* { dg-final { scan-tree-dump-not {want to version} "lversion" } } */ +/* { dg-final { scan-tree-dump-not {versioned} "lversion" } } */