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| author | Jakub Jelinek <jakub@redhat.com> | 2017-12-19 19:10:04 +0100 |
|---|---|---|
| committer | Jakub Jelinek <jakub@gcc.gnu.org> | 2017-12-19 19:10:04 +0100 |
| commit | ad2a970f7973708ea3359c0b8cc2aec7c9ead1bb (patch) | |
| tree | 85036f703ba660c24e544e555845177131f2ea78 /gcc | |
| parent | 4c9aa2cf8e59317ae73151c53fe84470b30c7ae9 (diff) | |
| download | gcc-ad2a970f7973708ea3359c0b8cc2aec7c9ead1bb.zip gcc-ad2a970f7973708ea3359c0b8cc2aec7c9ead1bb.tar.gz gcc-ad2a970f7973708ea3359c0b8cc2aec7c9ead1bb.tar.bz2 | |
re PR tree-optimization/83444 (missing strlen optimization on a member array of a local struct)
PR tree-optimization/83444
* tree-ssa-strlen.c (strlen_check_and_optimize_stmt): For the
character load case, if get_stridx on MEM_REF's operand doesn't
look usable, retry with get_addr_stridx.
* gcc.dg/strlenopt-38.c: New test.
From-SVN: r255835
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 3 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/strlenopt-38.c | 11 | ||||
| -rw-r--r-- | gcc/tree-ssa-strlen.c | 19 |
4 files changed, 37 insertions, 3 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 328ce28..5e8e9bf 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2017-12-19 Jakub Jelinek <jakub@redhat.com> + + PR tree-optimization/83444 + * tree-ssa-strlen.c (strlen_check_and_optimize_stmt): For the + character load case, if get_stridx on MEM_REF's operand doesn't + look usable, retry with get_addr_stridx. + 2017-12-19 Alexandre Oliva <aoliva@redhat.com> PR debug/83422 diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 81f96c6..1146e94 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -5,6 +5,9 @@ 2017-12-19 Jakub Jelinek <jakub@redhat.com> + PR tree-optimization/83444 + * gcc.dg/strlenopt-38.c: New test. + PR testsuite/83454 * gcc.dg/tree-ssa/cswtch-4.c: Require nonpic effective target. * gcc.dg/tree-ssa/cswtch-5.c: Likewise. diff --git a/gcc/testsuite/gcc.dg/strlenopt-38.c b/gcc/testsuite/gcc.dg/strlenopt-38.c index 3b698f9..7c39f3a 100644 --- a/gcc/testsuite/gcc.dg/strlenopt-38.c +++ b/gcc/testsuite/gcc.dg/strlenopt-38.c @@ -36,3 +36,14 @@ baz (void) if (s.b[0] != 0) abort (); } + +void +boo (void) +{ + struct S s; + strcpy (s.b, "012"); + strcpy (s.c, ""); + strcpy (s.b, s.c); + if (strlen (s.b) != 0) + abort (); +} diff --git a/gcc/tree-ssa-strlen.c b/gcc/tree-ssa-strlen.c index a2d514c..8971c7d 100644 --- a/gcc/tree-ssa-strlen.c +++ b/gcc/tree-ssa-strlen.c @@ -3155,14 +3155,27 @@ strlen_check_and_optimize_stmt (gimple_stmt_iterator *gsi) { tree off = integer_zero_node; unsigned HOST_WIDE_INT coff = 0; - int idx = -1; + int idx = 0; tree rhs1 = gimple_assign_rhs1 (stmt); if (code == MEM_REF) { idx = get_stridx (TREE_OPERAND (rhs1, 0)); - off = TREE_OPERAND (rhs1, 1); + if (idx > 0) + { + strinfo *si = get_strinfo (idx); + if (si + && si->nonzero_chars + && TREE_CODE (si->nonzero_chars) == INTEGER_CST + && (wi::to_widest (si->nonzero_chars) + >= wi::to_widest (off))) + off = TREE_OPERAND (rhs1, 1); + else + /* This case is not useful. See if get_addr_stridx + returns something usable. */ + idx = 0; + } } - else + if (idx <= 0) idx = get_addr_stridx (rhs1, NULL_TREE, &coff); if (idx > 0) { |