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author | Roger Sayle <roger@nextmovesoftware.com> | 2021-08-24 02:59:02 +0100 |
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committer | Roger Sayle <roger@nextmovesoftware.com> | 2021-08-24 02:59:02 +0100 |
commit | 78fa5112b4c2dcd94b78ee79baddebbf14d6ad98 (patch) | |
tree | 365cb89be7786601b7ba46c76eb7b21b74a9cb90 /gcc | |
parent | 819b7c3a339e3bdaf85cd55954c5536bd98aae09 (diff) | |
download | gcc-78fa5112b4c2dcd94b78ee79baddebbf14d6ad98.zip gcc-78fa5112b4c2dcd94b78ee79baddebbf14d6ad98.tar.gz gcc-78fa5112b4c2dcd94b78ee79baddebbf14d6ad98.tar.bz2 |
[Committed] PR middle-end/102029: Stricter typing in LSHIFT_EXPR sign folding.
My sincere apologies to everyone (again). As diagnosed by
Jakub Jelinek, my recent patch to fold the signedness of LSHIFT_EXPR
needs to be careful not to attempt transforming a left shift in an
integer type into an invalid left shift of a pointer type.
2021-08-24 Roger Sayle <roger@nextmovesoftware.com>
Jakub Jelinek <jakub@redhat.com>
gcc/ChangeLog
PR middle-end/102029
* match.pd (shift transformations): Add an additional check for
!POINTER_TYPE_P in the recently added left shift transformation.
gcc/testsuite/ChangeLog
PR middle-end/102029
* gcc.dg/fold-convlshift-3.c: New test case.
Diffstat (limited to 'gcc')
-rw-r--r-- | gcc/match.pd | 4 | ||||
-rw-r--r-- | gcc/testsuite/gcc.dg/fold-convlshift-3.c | 8 |
2 files changed, 11 insertions, 1 deletions
diff --git a/gcc/match.pd b/gcc/match.pd index 978a1b0..e5bbb12 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -3389,7 +3389,9 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) the form that minimizes the number of conversions. */ (simplify (convert (lshift:s@0 (convert:s@1 @2) INTEGER_CST@3)) - (if (tree_nop_conversion_p (type, TREE_TYPE (@0)) + (if (INTEGRAL_TYPE_P (type) + && !POINTER_TYPE_P (type) + && tree_nop_conversion_p (type, TREE_TYPE (@0)) && INTEGRAL_TYPE_P (TREE_TYPE (@2)) && TYPE_PRECISION (TREE_TYPE (@2)) <= TYPE_PRECISION (type)) (lshift (convert @2) @3))) diff --git a/gcc/testsuite/gcc.dg/fold-convlshift-3.c b/gcc/testsuite/gcc.dg/fold-convlshift-3.c new file mode 100644 index 0000000..8d01191 --- /dev/null +++ b/gcc/testsuite/gcc.dg/fold-convlshift-3.c @@ -0,0 +1,8 @@ +/* PR middle-end/102029 */ +/* { dg-do compile } */ +/* { dg-options "-O2" } */ +int * +foo (const __PTRDIFF_TYPE__ l) +{ + return (int *) (l << 2); +} |