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| author | Richard Biener <rguenther@suse.de> | 2023-10-23 11:25:17 +0200 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2023-10-23 12:32:00 +0200 |
| commit | d96bd4aade170fcd86f5f09b68b770dde798e631 (patch) | |
| tree | 7c279d74aa1be4649df8b1bcf93af9b2a22a4cd7 | |
| parent | 0c4bd1321a6def5eb44c530e83b01a415633b660 (diff) | |
| download | gcc-d96bd4aade170fcd86f5f09b68b770dde798e631.zip gcc-d96bd4aade170fcd86f5f09b68b770dde798e631.tar.gz gcc-d96bd4aade170fcd86f5f09b68b770dde798e631.tar.bz2 | |
tree-optimization/111917 - bougs IL after guard hoisting
The unswitching code to hoist guards inserts conditions in wrong
places. The following fixes this, simplifying code.
PR tree-optimization/111917
* tree-ssa-loop-unswitch.cc (hoist_guard): Always insert
new conditional after last stmt.
* gcc.dg/torture/pr111917.c: New testcase.
| -rw-r--r-- | gcc/testsuite/gcc.dg/torture/pr111917.c | 23 | ||||
| -rw-r--r-- | gcc/tree-ssa-loop-unswitch.cc | 5 |
2 files changed, 24 insertions, 4 deletions
diff --git a/gcc/testsuite/gcc.dg/torture/pr111917.c b/gcc/testsuite/gcc.dg/torture/pr111917.c new file mode 100644 index 0000000..532e302 --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr111917.c @@ -0,0 +1,23 @@ +/* { dg-do compile } */ +/* { dg-additional-options "-funswitch-loops" } */ + +long t; +long a() { + long b = t, c = t; + for (; b < 31; b++) + c <<= 1; + return c; +} +long t1; +static +int d() { + if (!t1) + return 0; +e: +f: + for (; a();) + ; + goto f; + return 0; +} +int main() { d(); } diff --git a/gcc/tree-ssa-loop-unswitch.cc b/gcc/tree-ssa-loop-unswitch.cc index 619b50f..b4611ac 100644 --- a/gcc/tree-ssa-loop-unswitch.cc +++ b/gcc/tree-ssa-loop-unswitch.cc @@ -1455,10 +1455,7 @@ hoist_guard (class loop *loop, edge guard) cond_stmt = as_a <gcond *> (stmt); extract_true_false_edges_from_block (guard_bb, &te, &fe); /* Insert guard to PRE_HEADER. */ - if (!empty_block_p (pre_header)) - gsi = gsi_last_bb (pre_header); - else - gsi = gsi_start_bb (pre_header); + gsi = gsi_last_bb (pre_header); /* Create copy of COND_STMT. */ new_cond_stmt = gimple_build_cond (gimple_cond_code (cond_stmt), gimple_cond_lhs (cond_stmt), |