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| author | Michael Matz <matz@suse.de> | 2005-04-20 14:30:38 +0000 |
|---|---|---|
| committer | Michael Matz <matz@gcc.gnu.org> | 2005-04-20 14:30:38 +0000 |
| commit | 687b527d75fed234ded60206c1b42a74f8e7fb39 (patch) | |
| tree | 3ce552dca407dedbb61dd41a3c35faecde16be70 /gcc | |
| parent | 71fc0c16760edea3b4d3c2afdda243bf8516df5c (diff) | |
| download | gcc-687b527d75fed234ded60206c1b42a74f8e7fb39.zip gcc-687b527d75fed234ded60206c1b42a74f8e7fb39.tar.gz gcc-687b527d75fed234ded60206c1b42a74f8e7fb39.tar.bz2 | |
re PR middle-end/20973 (kdelibs (khtml) miscompiled by reload)
PR20973
* reload.c (push_reload, find_dummy_reload): Check for uninitialized
pseudos.
From-SVN: r98460
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/reload.c | 19 |
2 files changed, 23 insertions, 2 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 03c3961..b6f7eab 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2005-04-20 Michael Matz <matz@suse.de> + + PR20973 + * reload.c (push_reload, find_dummy_reload): Check for uninitialized + pseudos. + 2005-04-20 Kazu Hirata <kazu@cs.umass.edu> * tree-ssa-phiopt.c: Fix comment typos. diff --git a/gcc/reload.c b/gcc/reload.c index 7d42492..2915475 100644 --- a/gcc/reload.c +++ b/gcc/reload.c @@ -1520,7 +1520,7 @@ push_reload (rtx in, rtx out, rtx *inloc, rtx *outloc, But if there is no spilling in this block, that is OK. An explicitly used hard reg cannot be a spill reg. */ - if (rld[i].reg_rtx == 0 && in != 0) + if (rld[i].reg_rtx == 0 && in != 0 && hard_regs_live_known) { rtx note; int regno; @@ -1534,6 +1534,11 @@ push_reload (rtx in, rtx out, rtx *inloc, rtx *outloc, && REG_P (XEXP (note, 0)) && (regno = REGNO (XEXP (note, 0))) < FIRST_PSEUDO_REGISTER && reg_mentioned_p (XEXP (note, 0), in) + /* Check that we don't use a hardreg for an uninitialized + pseudo. See also find_dummy_reload(). */ + && (ORIGINAL_REGNO (XEXP (note, 0)) < FIRST_PSEUDO_REGISTER + || ! bitmap_bit_p (ENTRY_BLOCK_PTR->global_live_at_end, + ORIGINAL_REGNO (XEXP (note, 0)))) && ! refers_to_regno_for_reload_p (regno, (regno + hard_regno_nregs[regno] @@ -1997,7 +2002,17 @@ find_dummy_reload (rtx real_in, rtx real_out, rtx *inloc, rtx *outloc, is a subreg, and in that case, out has a real mode. */ (GET_MODE (out) != VOIDmode - ? GET_MODE (out) : outmode))) + ? GET_MODE (out) : outmode)) + /* But only do all this if we can be sure, that this input + operand doesn't correspond with an uninitialized pseudoreg. + global can assign some hardreg to it, which is the same as + a different pseudo also currently live (as it can ignore the + conflict). So we never must introduce writes to such hardregs, + as they would clobber the other live pseudo using the same. + See also PR20973. */ + && (ORIGINAL_REGNO (in) < FIRST_PSEUDO_REGISTER + || ! bitmap_bit_p (ENTRY_BLOCK_PTR->global_live_at_end, + ORIGINAL_REGNO (in)))) { unsigned int regno = REGNO (in) + in_offset; unsigned int nwords = hard_regno_nregs[regno][inmode]; |