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| author | Steven Bosscher <steven@gcc.gnu.org> | 2012-11-12 20:21:59 +0000 |
|---|---|---|
| committer | Steven Bosscher <steven@gcc.gnu.org> | 2012-11-12 20:21:59 +0000 |
| commit | 211d71a745167d6bb935ddf21b7d7f6dd5168969 (patch) | |
| tree | e07507a7438788aa1e87722aa4308905bc85b8d3 /gcc/dce.c | |
| parent | 06b1198f7584b1e1cec68f96b9525629d6beeab0 (diff) | |
| download | gcc-211d71a745167d6bb935ddf21b7d7f6dd5168969.zip gcc-211d71a745167d6bb935ddf21b7d7f6dd5168969.tar.gz gcc-211d71a745167d6bb935ddf21b7d7f6dd5168969.tar.bz2 | |
re PR rtl-optimization/51447 (global register variable definition incorrectly removed as dead code)
gcc/
PR rtl-optimization/51447
* df-scan.c (df_get_entry_block_def_set): Add global regs to the set.
* df-problems.c (df_lr_local_compute): Make global regs always live.
* dce.c (deletable_insn_p): Make insns setting a global reg
inherently necessary.
testsuite/
PR rtl-optimization/51447
* gcc.c-torture/execute/pr51447.c: New test.
From-SVN: r193453
Diffstat (limited to 'gcc/dce.c')
| -rw-r--r-- | gcc/dce.c | 6 |
1 files changed, 6 insertions, 0 deletions
@@ -121,6 +121,12 @@ deletable_insn_p (rtx insn, bool fast, bitmap arg_stores) && !insn_nothrow_p (insn)) return false; + /* If INSN sets a global_reg, leave it untouched. */ + for (df_ref *def_rec = DF_INSN_DEFS (insn); *def_rec; def_rec++) + if (HARD_REGISTER_NUM_P (DF_REF_REGNO (*def_rec)) + && global_regs[DF_REF_REGNO (*def_rec)]) + return false; + body = PATTERN (insn); switch (GET_CODE (body)) { |