diff options
Diffstat (limited to 'gcc/simplify-rtx.c')
| -rw-r--r-- | gcc/simplify-rtx.c | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c index eb747ad3c86..42b1be60b15 100644 --- a/gcc/simplify-rtx.c +++ b/gcc/simplify-rtx.c @@ -2777,7 +2777,7 @@ simplify_binary_operation_1 (enum rtx_code code, enum machine_mode mode, } } } - else + else if (SCALAR_INT_MODE_P (mode)) { /* 0/x is 0 (or x&0 if x has side-effects). */ if (trueop0 == CONST0_RTX (mode) @@ -4177,10 +4177,20 @@ simplify_relational_operation_1 (enum rtx_code code, enum machine_mode mode, { rtx x = XEXP (op0, 0); rtx c = XEXP (op0, 1); + enum rtx_code invcode = op0code == PLUS ? MINUS : PLUS; + rtx tem = simplify_gen_binary (invcode, cmp_mode, op1, c); + + /* Detect an infinite recursive condition, where we oscillate at this + simplification case between: + A + B == C <---> C - B == A, + where A, B, and C are all constants with non-simplifiable expressions, + usually SYMBOL_REFs. */ + if (GET_CODE (tem) == invcode + && CONSTANT_P (x) + && rtx_equal_p (c, XEXP (tem, 1))) + return NULL_RTX; - c = simplify_gen_binary (op0code == PLUS ? MINUS : PLUS, - cmp_mode, op1, c); - return simplify_gen_relational (code, mode, cmp_mode, x, c); + return simplify_gen_relational (code, mode, cmp_mode, x, tem); } /* (ne:SI (zero_extract:SI FOO (const_int 1) BAR) (const_int 0))) is |