commit e150cbf591759af10f3d57acbe0eb381aafa00de Author: Richard Biener Date: Thu Aug 17 13:10:14 2023 +0200 tree-optimization/111039 - abnormals and bit test merging The following guards the bit test merging code in if-combine against the appearance of SSA names used in abnormal PHIs. PR tree-optimization/111039 * tree-ssa-ifcombine.cc (ifcombine_ifandif): Check for SSA_NAME_OCCURS_IN_ABNORMAL_PHI. * gcc.dg/pr111039.c: New testcase. (cherry picked from commit 482551a79a3d3f107f6239679ee74655cfe8707e) diff --git a/gcc/testsuite/gcc.dg/pr111039.c b/gcc/testsuite/gcc.dg/pr111039.c new file mode 100644 index 00000000000..bec9983b35f --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr111039.c @@ -0,0 +1,15 @@ +/* { dg-do compile } */ +/* { dg-options "-O" } */ + +int _setjmp (); +void abcd (); +void abcde (); +void compiler_corruption_function(int flags) +{ + int nowait = flags & 1048576, isexpand = flags & 8388608; + abcd(); + _setjmp(flags); + if (nowait && isexpand) + flags &= 0; + abcde(); +} --- a/gcc/tree-ssa-ifcombine.c +++ b/gcc/tree-ssa-ifcombine.c @@ -407,6 +407,9 @@ ifcombine_ifandif (basic_block inner_con { tree t, t2; + if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (name1)) + return false; + /* Do it. */ gsi = gsi_for_stmt (inner_cond); t = fold_build2 (LSHIFT_EXPR, TREE_TYPE (name1), @@ -457,6 +460,10 @@ ifcombine_ifandif (basic_block inner_con gimple_stmt_iterator gsi; tree t; + if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (name1) + || SSA_NAME_OCCURS_IN_ABNORMAL_PHI (name2)) + return false; + /* Find the common name which is bit-tested. */ if (name1 == name2) ;