diff options
| author | Andrew Pinski <apinski@marvell.com> | 2021-11-19 01:42:41 +0000 |
|---|---|---|
| committer | Andrew Pinski <apinski@marvell.com> | 2021-11-19 12:06:43 +0000 |
| commit | ea2954df43d4162af23a20c84f4c5485463977ac (patch) | |
| tree | 0c386e398ebd235fc0305681cb9df9671bcef4ad | |
| parent | 74a4ece02df1b1b6f396fd0e24dbbf8b0897858a (diff) | |
| download | gcc-ea2954df43d4162af23a20c84f4c5485463977ac.zip gcc-ea2954df43d4162af23a20c84f4c5485463977ac.tar.gz gcc-ea2954df43d4162af23a20c84f4c5485463977ac.tar.bz2 | |
Fix tree-optimization/103314 : Limit folding of (type) X op CST where type is a nop convert to gimple
There is some re-association code in fold_binary which conflicts with
this optimization due keeping around some "constants" which are not
INTEGER_CST (1 << -1) so we end up in an infinite loop because of that.
So we need to limit this case to GIMPLE level only.
OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.
PR tree-optimization/103314
gcc/ChangeLog:
* match.pd ((type) X op CST): Restrict the equal
TYPE_PRECISION case to GIMPLE only.
gcc/testsuite/ChangeLog:
* gcc.c-torture/compile/pr103314-1.c: New test.
| -rw-r--r-- | gcc/match.pd | 6 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.c-torture/compile/pr103314-1.c | 6 |
2 files changed, 11 insertions, 1 deletions
diff --git a/gcc/match.pd b/gcc/match.pd index 4042b53..e5985de 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -1619,7 +1619,11 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) after hoisting the conversion the operation will be narrower. It is also a good if the conversion is a nop as moves the conversion to one side; allowing for combining of the conversions. */ - TYPE_PRECISION (TREE_TYPE (@0)) <= TYPE_PRECISION (type) + TYPE_PRECISION (TREE_TYPE (@0)) < TYPE_PRECISION (type) + /* The conversion check for being a nop can only be done at the gimple + level as fold_binary has some re-association code which can conflict + with this if there is a "constant" which is not a full INTEGER_CST. */ + || (GIMPLE && TYPE_PRECISION (TREE_TYPE (@0)) == TYPE_PRECISION (type)) /* It's also a good idea if the conversion is to a non-integer mode. */ || GET_MODE_CLASS (TYPE_MODE (type)) != MODE_INT diff --git a/gcc/testsuite/gcc.c-torture/compile/pr103314-1.c b/gcc/testsuite/gcc.c-torture/compile/pr103314-1.c new file mode 100644 index 0000000..f4a6313 --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/compile/pr103314-1.c @@ -0,0 +1,6 @@ +/* { dg-options "" } */ +int main() { + int t = 1; + unsigned c = 0, d1 = t ? 1 ^ c ^ 1 >> (-1) : 0; /* { dg-warning "is negative" } */ + return d1; +} |