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| author | Richard Biener <rguenther@suse.de> | 2018-04-09 13:27:33 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2018-04-09 13:27:33 +0000 |
| commit | 46e58e180d6ab1fa37acc96f0b8cbf569bbf4105 (patch) | |
| tree | 0e7725d434692876e63909c136cabd1e84fc7237 /gcc | |
| parent | f04fd9038ee58325748fea2f085d43eddcdb37ad (diff) | |
| download | gcc-46e58e180d6ab1fa37acc96f0b8cbf569bbf4105.zip gcc-46e58e180d6ab1fa37acc96f0b8cbf569bbf4105.tar.gz gcc-46e58e180d6ab1fa37acc96f0b8cbf569bbf4105.tar.bz2 | |
re PR tree-optimization/85284 (Loop miscompilation starting with r238367)
2018-04-09 Richard Biener <rguenther@suse.de>
PR tree-optimization/85284
* tree-ssa-loop-niter.c (number_of_iterations_exit_assumptions):
Only use the niter constraining form of simple_iv when the exit
is always executed.
* gcc.dg/torture/pr85284.c: New testcase.
From-SVN: r259234
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/torture/pr85284.c | 20 | ||||
| -rw-r--r-- | gcc/tree-ssa-loop-niter.c | 4 |
4 files changed, 34 insertions, 2 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 165b968..6d0a269 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2018-04-09 Richard Biener <rguenther@suse.de> + + PR tree-optimization/85284 + * tree-ssa-loop-niter.c (number_of_iterations_exit_assumptions): + Only use the niter constraining form of simple_iv when the exit + is always executed. + 2018-04-09 Tom de Vries <tom@codesourcery.com> PR target/84041 diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index f89ddfe..6798e3b 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2018-04-09 Richard Biener <rguenther@suse.de> + + PR tree-optimization/85284 + * gcc.dg/torture/pr85284.c: New testcase. + 2018-04-09 Andrey Belevantsev <abel@ispras.ru> PR rtl-optimization/80463 diff --git a/gcc/testsuite/gcc.dg/torture/pr85284.c b/gcc/testsuite/gcc.dg/torture/pr85284.c new file mode 100644 index 0000000..80e2c5b --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr85284.c @@ -0,0 +1,20 @@ +/* { dg-do run } */ + +static int p[48], v; + +int +main () +{ + p[32] = 1; + for (int i = 48; i--;) + { + if (!p[i]) + continue; + if ((i & 7) > 2) + break; + v = i & 1; + } + if (v != 0) + __builtin_abort (); + return 0; +} diff --git a/gcc/tree-ssa-loop-niter.c b/gcc/tree-ssa-loop-niter.c index fa49abf..7a54c5f 100644 --- a/gcc/tree-ssa-loop-niter.c +++ b/gcc/tree-ssa-loop-niter.c @@ -2356,11 +2356,11 @@ number_of_iterations_exit_assumptions (struct loop *loop, edge exit, tree iv0_niters = NULL_TREE; if (!simple_iv_with_niters (loop, loop_containing_stmt (stmt), - op0, &iv0, &iv0_niters, false)) + op0, &iv0, safe ? &iv0_niters : NULL, false)) return false; tree iv1_niters = NULL_TREE; if (!simple_iv_with_niters (loop, loop_containing_stmt (stmt), - op1, &iv1, &iv1_niters, false)) + op1, &iv1, safe ? &iv1_niters : NULL, false)) return false; /* Give up on complicated case. */ if (iv0_niters && iv1_niters) |