diff options
| author | Bernd Schmidt <bernds@redhat.com> | 2017-01-23 16:30:55 +0000 |
|---|---|---|
| committer | Bernd Schmidt <bernds@gcc.gnu.org> | 2017-01-23 16:30:55 +0000 |
| commit | 427ed3ae3ed40c00540af45ecc15a2d1f4058268 (patch) | |
| tree | c331f74d4cc2a795f59daef6006982091f4a2dba /gcc/combine.c | |
| parent | e9c4fbe9c1eff61ffe2aa31c67cef2ffd346f674 (diff) | |
| download | gcc-427ed3ae3ed40c00540af45ecc15a2d1f4058268.zip gcc-427ed3ae3ed40c00540af45ecc15a2d1f4058268.tar.gz gcc-427ed3ae3ed40c00540af45ecc15a2d1f4058268.tar.bz2 | |
re PR rtl-optimization/71724 (ICE: Segmentation fault, deep recursion between combine_simplify_rtx and subst)
PR rtl-optimization/71724
* combine.c (if_then_else_cond): Look for situations where it is
beneficial to undo the work of one of the recursive calls.
From-SVN: r244817
Diffstat (limited to 'gcc/combine.c')
| -rw-r--r-- | gcc/combine.c | 26 |
1 files changed, 23 insertions, 3 deletions
diff --git a/gcc/combine.c b/gcc/combine.c index 28133ff..c643a0e 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -9044,11 +9044,31 @@ if_then_else_cond (rtx x, rtx *ptrue, rtx *pfalse) the same value, compute the new true and false values. */ else if (BINARY_P (x)) { - cond0 = if_then_else_cond (XEXP (x, 0), &true0, &false0); - cond1 = if_then_else_cond (XEXP (x, 1), &true1, &false1); + rtx op0 = XEXP (x, 0); + rtx op1 = XEXP (x, 1); + cond0 = if_then_else_cond (op0, &true0, &false0); + cond1 = if_then_else_cond (op1, &true1, &false1); + + if ((cond0 != 0 && cond1 != 0 && !rtx_equal_p (cond0, cond1)) + && (REG_P (op0) || REG_P (op1))) + { + /* Try to enable a simplification by undoing work done by + if_then_else_cond if it converted a REG into something more + complex. */ + if (REG_P (op0)) + { + cond0 = 0; + true0 = false0 = op0; + } + else + { + cond1 = 0; + true1 = false1 = op1; + } + } if ((cond0 != 0 || cond1 != 0) - && ! (cond0 != 0 && cond1 != 0 && ! rtx_equal_p (cond0, cond1))) + && ! (cond0 != 0 && cond1 != 0 && !rtx_equal_p (cond0, cond1))) { /* If if_then_else_cond returned zero, then true/false are the same rtl. We must copy one of them to prevent invalid rtl |