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| author | Richard Biener <rguenther@suse.de> | 2013-10-21 11:34:04 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2013-10-21 11:34:04 +0000 |
| commit | d480e6a572799f809744075cdf447f959753b173 (patch) | |
| tree | d39c87a3db103241526f21769916ac517ea36d8f /gcc | |
| parent | 54f9aba03140c7cdace8ff3c6847af855764656f (diff) | |
| download | gcc-d480e6a572799f809744075cdf447f959753b173.zip gcc-d480e6a572799f809744075cdf447f959753b173.tar.gz gcc-d480e6a572799f809744075cdf447f959753b173.tar.bz2 | |
re PR middle-end/58742 (pointer arithmetic simplification)
2013-10-21 Richard Biener <rguenther@suse.de>
PR middle-end/58742
* fold-const.c (fold_binary_loc): Fold ((T) (X /[ex] C)) * C
to (T) X for sign-changing conversions (or no conversion).
* c-c++-common/fold-divmul-1.c: New testcase.
From-SVN: r203890
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/fold-const.c | 7 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/c-c++-common/fold-divmul-1.c | 11 |
4 files changed, 29 insertions, 0 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index bbcc371..99b921a 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2013-10-21 Richard Biener <rguenther@suse.de> + + PR middle-end/58742 + * fold-const.c (fold_binary_loc): Fold ((T) (X /[ex] C)) * C + to (T) X for sign-changing conversions (or no conversion). + 2013-10-20 Uros Bizjak <ubizjak@gmail.com> * config/i386/i386.md (kxnor<mode>): Add FLAGS_REG clobber. diff --git a/gcc/fold-const.c b/gcc/fold-const.c index c4c09b6..2a18410 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -11002,6 +11002,13 @@ fold_binary_loc (location_t loc, fold_build2_loc (loc, MULT_EXPR, type, build_int_cst (type, 2) , arg1)); + /* ((T) (X /[ex] C)) * C cancels out if the conversion is + sign-changing only. */ + if (TREE_CODE (arg1) == INTEGER_CST + && TREE_CODE (arg0) == EXACT_DIV_EXPR + && operand_equal_p (arg1, TREE_OPERAND (arg0, 1), 0)) + return fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0)); + strict_overflow_p = false; if (TREE_CODE (arg1) == INTEGER_CST && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE, diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 7acbd3b..6add22c 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2013-10-21 Richard Biener <rguenther@suse.de> + + PR middle-end/58742 + * c-c++-common/fold-divmul-1.c: New testcase. + 2013-10-21 Michael Zolotukhin <michael.v.zolotukhin@gmail.com> * gcc.target/i386/memset-vector_loop-1.c: New test. diff --git a/gcc/testsuite/c-c++-common/fold-divmul-1.c b/gcc/testsuite/c-c++-common/fold-divmul-1.c new file mode 100644 index 0000000..5c86792 --- /dev/null +++ b/gcc/testsuite/c-c++-common/fold-divmul-1.c @@ -0,0 +1,11 @@ +/* { dg-do compile } */ +/* { dg-options "-fdump-tree-original" } */ + +int * +fx (int *b, int *e) +{ + return b + (e - b); +} + +/* { dg-final { scan-tree-dump-not "/\\\[ex\\\]" "original" } } */ +/* { dg-final { cleanup-tree-dump "original" } } */ |