From: Pan Li <pan2.li@intel.com>
Date: Fri, 11 Jul 2025 00:38:09 +0000 (+0800)
Subject: Match: Refine the widen mul check for SAT_MUL pattern
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f01216a0b71a3e88c796ed302d6a6bc2fdb35d44;p=thirdparty%2Fgcc.git

Match: Refine the widen mul check for SAT_MUL pattern

The widen mul will have source type from N-bits to
dest type 2N-bits.  The previous check only focus on
the HOST_WIDE_INT but not working for QI => HI, HI => SI
and SI to DImode.  Thus, refine the widen mul precision
check as dest has twice bits of input.

gcc/ChangeLog:

	* match.pd: Make sure widen mul has twice bitsize
	of the inputs in SAT_MUL pattern.

Signed-off-by: Pan Li <pan2.li@intel.com>
---

diff --git a/gcc/match.pd b/gcc/match.pd
index 67b33eee5f7..7f84d5149f4 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -3605,11 +3605,10 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
       unsigned widen_prec = TYPE_PRECISION (TREE_TYPE (@3));
       unsigned cvt5_prec = TYPE_PRECISION (TREE_TYPE (@5));
       unsigned cvt6_prec = TYPE_PRECISION (TREE_TYPE (@6));
-      unsigned hw_int_prec = sizeof (HOST_WIDE_INT) * 8;
       wide_int c2 = wi::to_wide (@2);
       wide_int max = wi::mask (prec, false, widen_prec);
       bool c2_is_max_p = wi::eq_p (c2, max);
-      bool widen_mult_p = cvt5_prec == cvt6_prec && hw_int_prec == cvt5_prec;
+      bool widen_mult_p = cvt5_prec == cvt6_prec && widen_prec == cvt6_prec * 2;
      }
      (if (widen_prec > prec && c2_is_max_p && widen_mult_p)))))
 )