[5/6] Bogus and missed folding on vector compares

Message ID 20230623082748.10FA71331F@imap2.suse-dmz.suse.de
State Accepted
Headers
Series [1/6] Avoid shorten_binary_op on VECTOR_TYPE |

Checks

Context Check Description
snail/gcc-patch-check success Github commit url

Commit Message

Richard Biener June 23, 2023, 8:27 a.m. UTC
  fold_binary tries to transform (double)float1 CMP (double)float2
into float1 CMP float2 but ends up using TYPE_PRECISION on the
argument types.  For vector types that compares the number of
lanes which should be always equal (so it's harmless as to
not generating wrong code).  The following instead properly
uses element_precision.

The same happens in the corresponding match.pd pattern.

Bootstrap and regtest ongoing on x86_64-unknown-linux-gnu, will
push after that finished.

	* fold-const.cc (fold_binary_loc): Use element_precision
	when trying (double)float1 CMP (double)float2 to
	float1 CMP float2 simplification.
	* match.pd: Likewise.
---
 gcc/fold-const.cc | 4 ++--
 gcc/match.pd      | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)
  

Patch

diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc
index 7e35eda7140..ac90a594fcc 100644
--- a/gcc/fold-const.cc
+++ b/gcc/fold-const.cc
@@ -12564,10 +12564,10 @@  fold_binary_loc (location_t loc, enum tree_code code, tree type,
 	tree targ1 = strip_float_extensions (arg1);
 	tree newtype = TREE_TYPE (targ0);
 
-	if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
+	if (element_precision (TREE_TYPE (targ1)) > element_precision (newtype))
 	  newtype = TREE_TYPE (targ1);
 
-	if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
+	if (element_precision (newtype) < element_precision (TREE_TYPE (arg0)))
 	  return fold_build2_loc (loc, code, type,
 			      fold_convert_loc (loc, newtype, targ0),
 			      fold_convert_loc (loc, newtype, targ1));
diff --git a/gcc/match.pd b/gcc/match.pd
index 2dd23826034..85d562a531d 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -6034,10 +6034,10 @@  DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
 	     type1 = double_type_node;
 	 }
       tree newtype
-        = (TYPE_PRECISION (TREE_TYPE (@00)) > TYPE_PRECISION (type1)
+        = (element_precision (TREE_TYPE (@00)) > element_precision (type1)
 	   ? TREE_TYPE (@00) : type1);
      }
-     (if (TYPE_PRECISION (TREE_TYPE (@0)) > TYPE_PRECISION (newtype))
+     (if (element_precision (TREE_TYPE (@0)) > element_precision (newtype))
       (cmp (convert:newtype @00) (convert:newtype @10))))))))