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| author | Franz Sirl <Franz.Sirl-kernel@lauterbach.com> | 2000-09-29 17:38:25 +0000 |
|---|---|---|
| committer | Franz Sirl <sirl@gcc.gnu.org> | 2000-09-29 17:38:25 +0000 |
| commit | 70dd0f7f41c65dd4162cc5184c519bfbec805cfb (patch) | |
| tree | 455b4ac10185b5208cea4d031dfc4e4e6be5f066 /gcc/loop.c | |
| parent | 0c6129af811f88b0ebabc443a29fb88ea44b52aa (diff) | |
| download | gcc-70dd0f7f41c65dd4162cc5184c519bfbec805cfb.zip gcc-70dd0f7f41c65dd4162cc5184c519bfbec805cfb.tar.gz gcc-70dd0f7f41c65dd4162cc5184c519bfbec805cfb.tar.bz2 | |
loop.c (check_final_value): A GIV is not replaceable if used before set.
2000-09-29 Franz Sirl <Franz.Sirl-kernel@lauterbach.com>
* loop.c (check_final_value): A GIV is not replaceable if used
before set.
From-SVN: r36668
Diffstat (limited to 'gcc/loop.c')
| -rw-r--r-- | gcc/loop.c | 25 |
1 files changed, 14 insertions, 11 deletions
@@ -5094,6 +5094,7 @@ check_final_value (loop, v) or all uses follow that insn in the same basic block), - its final value can be calculated (this condition is different than the one above in record_giv) + - it's not used before the it's set - no assignments to the biv occur during the giv's lifetime. */ #if 0 @@ -5105,7 +5106,7 @@ check_final_value (loop, v) if ((final_value = final_giv_value (loop, v)) && (v->always_computable || last_use_this_basic_block (v->dest_reg, v->insn))) { - int biv_increment_seen = 0; + int biv_increment_seen = 0, before_giv_insn = 0; rtx p = v->insn; rtx last_giv_use; @@ -5135,7 +5136,10 @@ check_final_value (loop, v) { p = NEXT_INSN (p); if (p == loop->end) - p = NEXT_INSN (loop->start); + { + before_giv_insn = 1; + p = NEXT_INSN (loop->start); + } if (p == v->insn) break; @@ -5153,7 +5157,7 @@ check_final_value (loop, v) if (reg_mentioned_p (v->dest_reg, PATTERN (p))) { - if (biv_increment_seen) + if (biv_increment_seen || before_giv_insn) { v->replaceable = 0; v->not_replaceable = 1; @@ -5438,14 +5442,13 @@ basic_induction_var (loop, x, mode, dest_reg, p, inc_val, mult_val, location) <= UNITS_PER_WORD) && (GET_MODE_CLASS (GET_MODE (SET_DEST (set))) == MODE_INT) - && SUBREG_REG (SET_DEST (set)) == x)) - && basic_induction_var (loop, SET_SRC (set), - (GET_MODE (SET_SRC (set)) == VOIDmode - ? GET_MODE (x) - : GET_MODE (SET_SRC (set))), - dest_reg, insn, - inc_val, mult_val, location)) - return 1; + && SUBREG_REG (SET_DEST (set)) == x))) + return basic_induction_var (loop, SET_SRC (set), + (GET_MODE (SET_SRC (set)) == VOIDmode + ? GET_MODE (x) + : GET_MODE (SET_SRC (set))), + dest_reg, insn, + inc_val, mult_val, location); } /* Fall through. */ |