[PATCH] Fix lots of uninitialized memory uses in sched_analyze_reg
Mon Mar 4 21:18:00 GMT 2013
Something that again hits lots of testcases during valgrind checking
bootstrap. init_alias_analysis apparently does
vec_safe_grow_cleared (reg_known_value, maxreg - FIRST_PSEUDO_REGISTER);
reg_known_equiv_p = sbitmap_alloc (maxreg - FIRST_PSEUDO_REGISTER);
but doesn't bitmap_clear (reg_known_equiv_p), perhaps as an optimization?
If set_reg_known_value is called (and not to the reg itself),
set_reg_known_equiv_p is called too though.
Right now get_reg_known_equiv_p is only called in one place, and we are only
interested in MEM_P known values there, so the following works fine.
Though perhaps if in the future we use the reg_known_equiv_p bitmap more,
we should bitmap_clear (reg_known_equiv_p) it instead.
Bootstrapped/regtested on x86_64-linux and i686-linux.
Ok for trunk (or do you prefer to slow down init_alias_analysis and just
clear the bitmap)?
2013-03-04 Jakub Jelinek <email@example.com>
* sched-deps.c (sched_analyze_reg): Only call get_reg_known_equiv_p
if get_reg_known_value returned non-NULL.
--- gcc/sched-deps.c.jj 2013-03-04 12:21:09.000000000 +0100
+++ gcc/sched-deps.c 2013-03-04 17:29:03.478944157 +0100
@@ -2351,10 +2351,10 @@ sched_analyze_reg (struct deps_desc *dep
/* Pseudos that are REG_EQUIV to something may be replaced
by that during reloading. We need only add dependencies for
the address in the REG_EQUIV note. */
- if (!reload_completed && get_reg_known_equiv_p (regno))
+ if (!reload_completed)
rtx t = get_reg_known_value (regno);
- if (MEM_P (t))
+ if (t && MEM_P (t) && get_reg_known_equiv_p (regno))
sched_analyze_2 (deps, XEXP (t, 0), insn);
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