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| author | Jakub Jelinek <jakub@redhat.com> | 2020-01-03 10:10:13 +0100 |
|---|---|---|
| committer | Jakub Jelinek <jakub@gcc.gnu.org> | 2020-01-03 10:10:13 +0100 |
| commit | 5a6e28b5bae7a236b35994d0f64fd902a574872c (patch) | |
| tree | b510442fd9cb403da9e8760e16a7fcc4b9468f45 /gcc/loop-iv.c | |
| parent | 4d124378848e82e58f1349b44822cc7b1210de1e (diff) | |
| download | gcc-5a6e28b5bae7a236b35994d0f64fd902a574872c.zip gcc-5a6e28b5bae7a236b35994d0f64fd902a574872c.tar.gz gcc-5a6e28b5bae7a236b35994d0f64fd902a574872c.tar.bz2 | |
re PR rtl-optimization/93088 (Compile time hog on gcc/testsuite/gcc.target/i386/pr56348.c w/ -O3 -funroll-loops -fno-tree-dominator-opts -fno-tree-vrp)
PR rtl-optimization/93088
* loop-iv.c (find_single_def_src): Punt after looking through
128 reg copies for regs with single definitions. Move definitions
to first uses.
* gcc.target/i386/pr93088.c: New test.
From-SVN: r279854
Diffstat (limited to 'gcc/loop-iv.c')
| -rw-r--r-- | gcc/loop-iv.c | 15 |
1 files changed, 7 insertions, 8 deletions
diff --git a/gcc/loop-iv.c b/gcc/loop-iv.c index 83c3eef..6a59954 100644 --- a/gcc/loop-iv.c +++ b/gcc/loop-iv.c @@ -1384,24 +1384,23 @@ simple_rhs_p (rtx rhs) static rtx find_single_def_src (unsigned int regno) { - df_ref adef; - rtx set, src; + rtx src = NULL_RTX; - for (;;) + /* Don't look through unbounded number of single definition REG copies, + there might be loops for sources with uninitialized variables. */ + for (int cnt = 0; cnt < 128; cnt++) { - rtx note; - adef = DF_REG_DEF_CHAIN (regno); + df_ref adef = DF_REG_DEF_CHAIN (regno); if (adef == NULL || DF_REF_NEXT_REG (adef) != NULL || DF_REF_IS_ARTIFICIAL (adef)) return NULL_RTX; - set = single_set (DF_REF_INSN (adef)); + rtx set = single_set (DF_REF_INSN (adef)); if (set == NULL || !REG_P (SET_DEST (set)) || REGNO (SET_DEST (set)) != regno) return NULL_RTX; - note = find_reg_equal_equiv_note (DF_REF_INSN (adef)); - + rtx note = find_reg_equal_equiv_note (DF_REF_INSN (adef)); if (note && function_invariant_p (XEXP (note, 0))) { src = XEXP (note, 0); |