From: Jan Beulich <jbeulich@suse.com>
Date: Wed, 12 Jul 2023 10:14:08 +0000 (+0200)
Subject: x86: make better use of VBROADCASTSS / VPBROADCASTD
X-Git-Tag: basepoints/gcc-15~7682
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=28cdba24a9b8405d9f4ec2591c53d23a8bb74051;p=thirdparty%2Fgcc.git

x86: make better use of VBROADCASTSS / VPBROADCASTD

... in vec_dupv4sf / *vec_dupv4si. The respective broadcast insns are
never longer (yet sometimes shorter) than the corresponding VSHUFPS /
VPSHUFD, due to the immediate operand of the shuffle insns balancing the
(uniform) need for VEX3 in the broadcast ones. When EVEX encoding is
respective the broadcast insns are always shorter.

Add new alternatives to cover the AVX2 and AVX512 cases as appropriate.

While touching this anyway, switch to consistently using "sseshuf1" in
the "type" attributes for all shuffle forms.

gcc/

	* config/i386/sse.md (vec_dupv4sf): Make first alternative use
	vbroadcastss for AVX2. New AVX512F alternative.
	(*vec_dupv4si): New AVX2 and AVX512F alternatives using
	vpbroadcastd. Replace sselog1 by sseshuf1 in "type" attribute.

gcc/testsuite/

	* gcc.target/i386/avx2-dupv4sf.c: New test.
	* gcc.target/i386/avx2-dupv4si.c: Likewise.
	* gcc.target/i386/avx512f-dupv4sf.c: Likewise.
	* gcc.target/i386/avx512f-dupv4si.c: Likewise.
---

diff --git a/gcc/config/i386/sse.md b/gcc/config/i386/sse.md
index 24359cd189c8..6bf9c99a2c12 100644
--- a/gcc/config/i386/sse.md
+++ b/gcc/config/i386/sse.md
@@ -26475,41 +26475,64 @@
 	(const_int 1)))])
 
 (define_insn "vec_dupv4sf"
-  [(set (match_operand:V4SF 0 "register_operand" "=v,v,x")
+  [(set (match_operand:V4SF 0 "register_operand" "=v,v,v,x")
 	(vec_duplicate:V4SF
-	  (match_operand:SF 1 "nonimmediate_operand" "Yv,m,0")))]
+	  (match_operand:SF 1 "nonimmediate_operand" "Yv,v,m,0")))]
   "TARGET_SSE"
   "@
-   vshufps\t{$0, %1, %1, %0|%0, %1, %1, 0}
+   * return TARGET_AVX2 ? \"vbroadcastss\t{%1, %0|%0, %1}\" : \"vshufps\t{$0, %d1, %0|%0, %d1, 0}\";
+   vbroadcastss\t{%1, %g0|%g0, %1}
    vbroadcastss\t{%1, %0|%0, %1}
    shufps\t{$0, %0, %0|%0, %0, 0}"
-  [(set_attr "isa" "avx,avx,noavx")
-   (set_attr "type" "sseshuf1,ssemov,sseshuf1")
-   (set_attr "length_immediate" "1,0,1")
-   (set_attr "prefix_extra" "0,1,*")
-   (set_attr "prefix" "maybe_evex,maybe_evex,orig")
-   (set_attr "mode" "V4SF")])
+  [(set_attr "isa" "avx,*,avx,noavx")
+   (set (attr "type")
+	(cond [(and (eq_attr "alternative" "0")
+		    (match_test "!TARGET_AVX2"))
+		 (const_string "sseshuf1")
+	       (eq_attr "alternative" "3")
+		 (const_string "sseshuf1")
+	      ]
+	      (const_string "ssemov")))
+   (set (attr "length_immediate")
+	(if_then_else (eq_attr "type" "sseshuf1")
+		      (const_string "1")
+		      (const_string "0")))
+   (set_attr "prefix_extra" "0,1,1,*")
+   (set_attr "prefix" "maybe_evex,evex,maybe_evex,orig")
+   (set_attr "mode" "V4SF,V16SF,V4SF,V4SF")
+   (set (attr "enabled")
+	(if_then_else (eq_attr "alternative" "1")
+		      (symbol_ref "TARGET_AVX512F && !TARGET_AVX512VL
+				   && !TARGET_PREFER_AVX256")
+		      (const_string "*")))])
 
 (define_insn "*vec_dupv4si"
-  [(set (match_operand:V4SI 0 "register_operand"     "=v,v,x")
+  [(set (match_operand:V4SI 0 "register_operand"     "=v,v,v,v,x")
 	(vec_duplicate:V4SI
-	  (match_operand:SI 1 "nonimmediate_operand" "Yv,m,0")))]
+	  (match_operand:SI 1 "nonimmediate_operand" "Yvm,v,Yv,m,0")))]
   "TARGET_SSE"
   "@
+   vpbroadcastd\t{%1, %0|%0, %1}
+   vpbroadcastd\t{%1, %g0|%g0, %1}
    %vpshufd\t{$0, %1, %0|%0, %1, 0}
    vbroadcastss\t{%1, %0|%0, %1}
    shufps\t{$0, %0, %0|%0, %0, 0}"
-  [(set_attr "isa" "sse2,avx,noavx")
-   (set_attr "type" "sselog1,ssemov,sselog1")
-   (set_attr "length_immediate" "1,0,1")
-   (set_attr "prefix_extra" "0,1,*")
-   (set_attr "prefix" "maybe_vex,maybe_evex,orig")
-   (set_attr "mode" "TI,V4SF,V4SF")
+  [(set_attr "isa" "avx2,*,sse2,avx,noavx")
+   (set_attr "type" "ssemov,ssemov,sseshuf1,ssemov,sseshuf1")
+   (set_attr "length_immediate" "0,0,1,0,1")
+   (set_attr "prefix_extra" "1,1,0,1,*")
+   (set_attr "prefix" "maybe_evex,evex,maybe_vex,maybe_evex,orig")
+   (set_attr "mode" "TI,XI,TI,V4SF,V4SF")
    (set (attr "preferred_for_speed")
-     (cond [(eq_attr "alternative" "1")
+     (cond [(eq_attr "alternative" "3")
 	      (symbol_ref "!TARGET_INTER_UNIT_MOVES_TO_VEC")
 	   ]
-	   (symbol_ref "true")))])
+	   (symbol_ref "true")))
+   (set (attr "enabled")
+	(if_then_else (eq_attr "alternative" "1")
+		      (symbol_ref "TARGET_AVX512F && !TARGET_AVX512VL
+				   && !TARGET_PREFER_AVX256")
+		      (const_string "*")))])
 
 (define_insn "*vec_dupv2di"
   [(set (match_operand:V2DI 0 "register_operand"     "=x,v,v,v,x")
diff --git a/gcc/testsuite/gcc.target/i386/avx2-dupv4sf.c b/gcc/testsuite/gcc.target/i386/avx2-dupv4sf.c
new file mode 100644
index 000000000000..9b45ee590853
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/avx2-dupv4sf.c
@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-mavx2 -O2" } */
+/* { dg-final { scan-assembler-times "vbroadcastss" 2 } } */
+
+typedef float __attribute__ ((vector_size (16))) v4sf;
+
+v4sf bcst_reg (float f)
+{
+  register float x asm ("xmm7") = f;
+
+  asm ("" : "+v" (x));
+  return (v4sf) {x, x, x, x};
+}
+
+v4sf bcst_mem (const float *f)
+{
+  return (v4sf) {*f, *f, *f, *f};
+}
diff --git a/gcc/testsuite/gcc.target/i386/avx2-dupv4si.c b/gcc/testsuite/gcc.target/i386/avx2-dupv4si.c
new file mode 100644
index 000000000000..ffe6318cdfcc
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/avx2-dupv4si.c
@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-mavx2 -O2" } */
+/* { dg-final { scan-assembler-times "vpbroadcastd" 2 } } */
+
+typedef int __attribute__ ((vector_size (16))) v4si;
+
+v4si bcst_reg (int i)
+{
+  register int x asm ("xmm7") = i;
+
+  asm ("" : "+v" (x));
+  return (v4si) {x, x, x, x};
+}
+
+v4si bcst_mem (const int *i)
+{
+  return (v4si) {*i, *i, *i, *i};
+}
diff --git a/gcc/testsuite/gcc.target/i386/avx512f-dupv4sf.c b/gcc/testsuite/gcc.target/i386/avx512f-dupv4sf.c
new file mode 100644
index 000000000000..2682fc6bee3f
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/avx512f-dupv4sf.c
@@ -0,0 +1,13 @@
+/* { dg-do compile { target { ! ia32 } } } */
+/* { dg-options "-mavx512f -mno-avx512vl -mprefer-vector-width=512 -O2" } */
+/* { dg-final { scan-assembler "vbroadcastss\[^\n\]*%xmm17, *%zmm" } } */
+
+typedef float __attribute__ ((vector_size (16))) v4sf;
+
+v4sf bcst (float f)
+{
+  register float x asm ("xmm17") = f;
+
+  asm ("" : "+v" (x));
+  return (v4sf) {x, x, x, x};
+}
diff --git a/gcc/testsuite/gcc.target/i386/avx512f-dupv4si.c b/gcc/testsuite/gcc.target/i386/avx512f-dupv4si.c
new file mode 100644
index 000000000000..dbf00d7fb823
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/avx512f-dupv4si.c
@@ -0,0 +1,13 @@
+/* { dg-do compile { target { ! ia32 } } } */
+/* { dg-options "-mavx512f -mno-avx512vl -mprefer-vector-width=512 -O2" } */
+/* { dg-final { scan-assembler "vpbroadcastd\[^\n\]*%xmm17, *%zmm" } } */
+
+typedef int __attribute__ ((vector_size (16))) v4si;
+
+v4si bcst (int i)
+{
+  register int x asm ("xmm17") = i;
+
+  asm ("" : "+v" (x));
+  return (v4si) {x, x, x, x};
+}