[PATCH] rs6000: Eliminate zext fed by vclzlsbb [PR111480]

["Kewen.Lin" <linkw@linux.ibm.com>]

Hi,

As PR111480 shows, commit r14-4079 only optimizes the case
of vctzlsbb but not for the similar vclzlsbb.  This patch
is to consider vclzlsbb as well and avoid the failure on
the reported test case.  It also simplifies the patterns
with iterator and attribute.

Bootstrapped and regtested on powerpc64-linux-gnu P8/P9
and powerpc64le-linux-gnu P9 and P10.

I'm going to push this soon.

BR,
Kewen
-----
	PR target/111480

gcc/ChangeLog:

	* config/rs6000/vsx.md (VCZLSBB): New int iterator.
	(vczlsbb_char): New int attribute.
	(vclzlsbb_<mode>, vctzlsbb_<mode>): Merge to ...
	(vc<vczlsbb_char>zlsbb_<mode>): ... this.
	(*vctzlsbb_zext_<mode>): Rename to ...
	(*vc<vczlsbb_char>zlsbb_zext_<mode>): ... this, and extend it to
	cover vclzlsbb.
---
 gcc/config/rs6000/vsx.md | 41 ++++++++++++++++++----------------------
 1 file changed, 18 insertions(+), 23 deletions(-)

diff --git a/gcc/config/rs6000/vsx.md b/gcc/config/rs6000/vsx.md
index 4c1725a7ecd..6111cc90eb7 100644
--- a/gcc/config/rs6000/vsx.md
+++ b/gcc/config/rs6000/vsx.md
@@ -411,6 +411,12 @@ (define_mode_attr VM3_char [(V2DI "d")
 			   (V2DF  "d")
 			   (V4SF  "w")])

+;; Iterator and attribute for vector count leading/trailing
+;; zero least-significant bits byte
+(define_int_iterator VCZLSBB [UNSPEC_VCLZLSBB
+			      UNSPEC_VCTZLSBB])
+(define_int_attr vczlsbb_char [(UNSPEC_VCLZLSBB "l")
+			       (UNSPEC_VCTZLSBB "t")])

 ;; VSX moves

@@ -5855,35 +5861,24 @@ (define_insn "vcmpnezw"
   "vcmpnezw %0,%1,%2"
   [(set_attr "type" "vecsimple")])

-;; Vector Count Leading Zero Least-Significant Bits Byte
-(define_insn "vclzlsbb_<mode>"
-  [(set (match_operand:SI 0 "register_operand" "=r")
-	(unspec:SI
-	 [(match_operand:VSX_EXTRACT_I 1 "altivec_register_operand" "v")]
-	 UNSPEC_VCLZLSBB))]
-  "TARGET_P9_VECTOR"
-  "vclzlsbb %0,%1"
-  [(set_attr "type" "vecsimple")])
-
-;; Vector Count Trailing Zero Least-Significant Bits Byte
-(define_insn "*vctzlsbb_zext_<mode>"
+;; Vector Count Leading/Trailing Zero Least-Significant Bits Byte
+(define_insn "*vc<vczlsbb_char>zlsbb_zext_<mode>"
   [(set (match_operand:DI 0 "register_operand" "=r")
-	(zero_extend:DI
-	(unspec:SI
-	 [(match_operand:VSX_EXTRACT_I 1 "altivec_register_operand" "v")]
-	 UNSPEC_VCTZLSBB)))]
+	  (zero_extend:DI
+	    (unspec:SI
+	      [(match_operand:VSX_EXTRACT_I 1 "altivec_register_operand" "v")]
+	      VCZLSBB)))]
   "TARGET_P9_VECTOR"
-  "vctzlsbb %0,%1"
+  "vc<vczlsbb_char>zlsbb %0,%1"
   [(set_attr "type" "vecsimple")])

-;; Vector Count Trailing Zero Least-Significant Bits Byte
-(define_insn "vctzlsbb_<mode>"
+(define_insn "vc<vczlsbb_char>zlsbb_<mode>"
   [(set (match_operand:SI 0 "register_operand" "=r")
-        (unspec:SI
-         [(match_operand:VSX_EXTRACT_I 1 "altivec_register_operand" "v")]
-         UNSPEC_VCTZLSBB))]
+	  (unspec:SI
+	    [(match_operand:VSX_EXTRACT_I 1 "altivec_register_operand" "v")]
+	    VCZLSBB))]
   "TARGET_P9_VECTOR"
-  "vctzlsbb %0,%1"
+  "vc<vczlsbb_char>zlsbb %0,%1"
   [(set_attr "type" "vecsimple")])

 ;; Vector Extract Unsigned Byte Left-Indexed
--
2.42.0