+2013-12-10 Eric Botcazou <ebotcazou@adacore.com>
+
+ PR rtl-optimization/58295
+ * simplify-rtx.c (simplify_truncation): Restrict the distribution for
+ WORD_REGISTER_OPERATIONS targets.
+
2013-12-10 Richard Sandiford <rdsandiford@googlemail.com>
* genrecog.c (validate_pattern): Treat all messages except missing
XEXP (op, 0), origmode);
}
- /* Simplify (truncate:SI (op:DI (x:DI) (y:DI)))
- to (op:SI (truncate:SI (x:DI)) (truncate:SI (x:DI))). */
- if (GET_CODE (op) == PLUS
- || GET_CODE (op) == MINUS
- || GET_CODE (op) == MULT)
+ /* If the machine can perform operations in the truncated mode, distribute
+ the truncation, i.e. simplify (truncate:QI (op:SI (x:SI) (y:SI))) into
+ (op:QI (truncate:QI (x:SI)) (truncate:QI (y:SI))). */
+ if (1
+#ifdef WORD_REGISTER_OPERATIONS
+ && precision >= BITS_PER_WORD
+#endif
+ && (GET_CODE (op) == PLUS
+ || GET_CODE (op) == MINUS
+ || GET_CODE (op) == MULT))
{
rtx op0 = simplify_gen_unary (TRUNCATE, mode, XEXP (op, 0), op_mode);
if (op0)