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| author | Roger Sayle <roger@eyesopen.com> | 2003-01-25 21:49:52 +0000 |
|---|---|---|
| committer | Roger Sayle <sayle@gcc.gnu.org> | 2003-01-25 21:49:52 +0000 |
| commit | 7821bfc741f6cdf7044997ce8a9e157920765c1a (patch) | |
| tree | 16a8b8743826b7fb1be29a0f0f140d95a6a88de1 /gcc | |
| parent | 5f0bea72c558bdd22238fffb4ba31d71221c473a (diff) | |
| download | gcc-7821bfc741f6cdf7044997ce8a9e157920765c1a.zip gcc-7821bfc741f6cdf7044997ce8a9e157920765c1a.tar.gz gcc-7821bfc741f6cdf7044997ce8a9e157920765c1a.tar.bz2 | |
gcse.c (bypass_last_basic_block): New global variable.
* gcse.c (bypass_last_basic_block): New global variable.
(bypass_block): Use redirect_edge_and_branch_force to redirect
fall-through edges. Use bypass_last_basic_block to determine
which blocks have valid PRE information.
(bypass_conditional_jumps): Initialize bypass_last_basic_block.
From-SVN: r61800
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 8 | ||||
| -rw-r--r-- | gcc/gcse.c | 27 |
2 files changed, 30 insertions, 5 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 9c7c804..b34f957 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +2003-01-25 Roger Sayle <roger@eyesopen.com> + + * gcse.c (bypass_last_basic_block): New global variable. + (bypass_block): Use redirect_edge_and_branch_force to redirect + fall-through edges. Use bypass_last_basic_block to determine + which blocks have valid PRE information. + (bypass_conditional_jumps): Initialize bypass_last_basic_block. + Sat Jan 25 22:31:59 CET 2003 Jan Hubicka <jh@suse.cz> * gcse.c (local_cprop_pass): Update reg_sets table when needed. @@ -4527,6 +4527,13 @@ one_cprop_pass (pass, cprop_jumps, bypass_jumps) /* Bypass conditional jumps. */ +/* The value of last_basic_block at the beginning of the jump_bypass + pass. The use of redirect_edge_and_branch_force may introduce new + basic blocks, but the data flow analysis is only valid for basic + block indices less than bypass_last_basic_block. */ + +static int bypass_last_basic_block; + /* Find a set of REGNO to a constant that is available at the end of basic block BB. Returns NULL if no such set is found. Based heavily upon find_avail_set. */ @@ -4597,6 +4604,13 @@ bypass_block (bb, setcc, jump) for (e = bb->pred; e; e = enext) { enext = e->pred_next; + if (e->flags & EDGE_COMPLEX) + continue; + + /* We can't redirect edges from new basic blocks. */ + if (e->src->index >= bypass_last_basic_block) + continue; + for (i = 0; i < reg_use_count; i++) { struct reg_use *reg_used = ®_use_table[i]; @@ -4630,12 +4644,13 @@ bypass_block (bb, setcc, jump) else dest = NULL; - /* Once basic block indices are stable, we should be able - to use redirect_edge_and_branch_force instead. */ old_dest = e->dest; - if (dest != NULL && dest != old_dest - && redirect_edge_and_branch (e, dest)) - { + if (dest != NULL + && dest != old_dest + && dest != EXIT_BLOCK_PTR) + { + redirect_edge_and_branch_force (e, dest); + /* Copy the register setter to the redirected edge. Don't copy CC0 setters, as CC0 is dead after jump. */ if (setcc) @@ -4679,6 +4694,8 @@ bypass_conditional_jumps () if (ENTRY_BLOCK_PTR->next_bb == EXIT_BLOCK_PTR) return 0; + bypass_last_basic_block = last_basic_block; + changed = 0; FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR->next_bb->next_bb, EXIT_BLOCK_PTR, next_bb) |