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| author | Richard Biener <rguenther@suse.de> | 2021-05-04 10:07:35 +0200 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2021-05-04 12:31:50 +0200 |
| commit | a310bb73edc9548e08d1fa28e7a56246caf27757 (patch) | |
| tree | 4494b14985d410f01d6ecb2f5616b3884aa0508f | |
| parent | 2326627eb19d8c21251fd60479f1a190621c475b (diff) | |
| download | gcc-a310bb73edc9548e08d1fa28e7a56246caf27757.zip gcc-a310bb73edc9548e08d1fa28e7a56246caf27757.tar.gz gcc-a310bb73edc9548e08d1fa28e7a56246caf27757.tar.bz2 | |
tree-optimization/100329 - avoid reassociating asm goto defs
This avoids reassociating asm goto defs because we have no idea
on which outgoing edge to insert defs.
2021-05-04 Richard Biener <rguenther@suse.de>
PR tree-optimization/100329
* tree-ssa-reassoc.c (can_reassociate_p): Do not reassociate
asm goto defs.
(insert_stmt_after): Assert we're not running into asm goto.
* gcc.dg/torture/pr100329.c: New testcase.
| -rw-r--r-- | gcc/testsuite/gcc.dg/torture/pr100329.c | 16 | ||||
| -rw-r--r-- | gcc/tree-ssa-reassoc.c | 10 |
2 files changed, 26 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.dg/torture/pr100329.c b/gcc/testsuite/gcc.dg/torture/pr100329.c new file mode 100644 index 0000000..b90700d --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr100329.c @@ -0,0 +1,16 @@ +/* { dg-do compile } */ +/* { dg-additional-options "--param tree-reassoc-width=2" } */ + +unsigned int a0; + +unsigned int +foo (unsigned int a1, unsigned int a2) +{ + unsigned int x; + + asm goto ("" : "=r" (x) : : : lab); + a0 = x; + + lab: + return x + a1 + a2 + 1; +} diff --git a/gcc/tree-ssa-reassoc.c b/gcc/tree-ssa-reassoc.c index 8e2a489..359367c 100644 --- a/gcc/tree-ssa-reassoc.c +++ b/gcc/tree-ssa-reassoc.c @@ -1446,6 +1446,10 @@ insert_stmt_after (gimple *stmt, gimple *insert_point) gsi_insert_after (&gsi, stmt, GSI_NEW_STMT); return; } + else if (gimple_code (insert_point) == GIMPLE_ASM) + /* We have no idea where to insert - it depends on where the + uses will be placed. */ + gcc_unreachable (); else /* We assume INSERT_POINT is a SSA_NAME_DEF_STMT of some SSA_NAME, thus if it must end a basic block, it should be a call that can @@ -5893,6 +5897,12 @@ can_reassociate_p (tree op) tree type = TREE_TYPE (op); if (TREE_CODE (op) == SSA_NAME && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (op)) return false; + /* Make sure asm goto outputs do not participate in reassociation since + we have no way to find an insertion place after asm goto. */ + if (TREE_CODE (op) == SSA_NAME + && gimple_code (SSA_NAME_DEF_STMT (op)) == GIMPLE_ASM + && gimple_asm_nlabels (as_a <gasm *> (SSA_NAME_DEF_STMT (op))) != 0) + return false; if ((ANY_INTEGRAL_TYPE_P (type) && TYPE_OVERFLOW_WRAPS (type)) || NON_SAT_FIXED_POINT_TYPE_P (type) || (flag_associative_math && FLOAT_TYPE_P (type))) |