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| author | Geoff Keating <geoffk@cygnus.com> | 1999-10-28 20:37:37 +0000 |
|---|---|---|
| committer | Geoffrey Keating <geoffk@gcc.gnu.org> | 1999-10-28 20:37:37 +0000 |
| commit | a6092975367388a74307ea5c40eb539ad83a1fb1 (patch) | |
| tree | 61d216c911f0d0d3176bf1ca4b90cc34802a10e7 /gcc | |
| parent | af05822029866791f4fb4a241ac5f0bc529c09cf (diff) | |
| download | gcc-a6092975367388a74307ea5c40eb539ad83a1fb1.zip gcc-a6092975367388a74307ea5c40eb539ad83a1fb1.tar.gz gcc-a6092975367388a74307ea5c40eb539ad83a1fb1.tar.bz2 | |
flow.c (propagate_block): When the last reference to a label before an ADDR_VEC is deleted because the...
* flow.c (propagate_block): When the last reference to a label
before an ADDR_VEC is deleted because the reference is a dead
store, delete the ADDR_VEC.
From-SVN: r30247
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/flow.c | 34 |
2 files changed, 40 insertions, 0 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 5595acc..97e54f5 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +Fri Oct 29 06:32:44 1999 Geoffrey Keating <geoffk@cygnus.com> + + * flow.c (propagate_block): When the last reference to a label + before an ADDR_VEC is deleted because the reference is a dead + store, delete the ADDR_VEC. + Thu Oct 28 12:28:50 1999 Richard Henderson <rth@cygnus.com> * resource.c (find_free_register): Don't use the frame pointer @@ -3321,6 +3321,40 @@ propagate_block (old, first, last, significant, bnum, flags) can cause trouble for first or last insn in a basic block. */ if ((flags & PROP_KILL_DEAD_CODE) && insn_is_dead) { + rtx inote; + /* If the insn referred to a label, note that the label is + now less used. */ + for (inote = REG_NOTES (insn); inote; inote = XEXP (inote, 1)) + { + if (REG_NOTE_KIND (inote) == REG_LABEL) + { + rtx label = XEXP (inote, 0); + rtx next; + LABEL_NUSES (label)--; + + /* If this label was attached to an ADDR_VEC, it's + safe to delete the ADDR_VEC. In fact, it's pretty much + mandatory to delete it, because the ADDR_VEC may + be referencing labels that no longer exist. */ + if (LABEL_NUSES (label) == 0 + && (next = next_nonnote_insn (label)) != NULL + && GET_CODE (next) == JUMP_INSN + && (GET_CODE (PATTERN (next)) == ADDR_VEC + || GET_CODE (PATTERN (next)) == ADDR_DIFF_VEC)) + { + rtx pat = PATTERN (next); + int diff_vec_p = GET_CODE (pat) == ADDR_DIFF_VEC; + int len = XVECLEN (pat, diff_vec_p); + int i; + for (i = 0; i < len; i++) + LABEL_NUSES (XEXP (XVECEXP (pat, diff_vec_p, i), 0))--; + PUT_CODE (next, NOTE); + NOTE_LINE_NUMBER (next) = NOTE_INSN_DELETED; + NOTE_SOURCE_FILE (next) = 0; + } + } + } + PUT_CODE (insn, NOTE); NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED; NOTE_SOURCE_FILE (insn) = 0; |