[gcc r12-6337] Optimize V16HF vector insert to element 0 for AVX2.

[gcc r12-6337] Optimize V16HF vector insert to element 0 for AVX2.

[hongtao Liu]

https://gcc.gnu.org/g:1f759dbdcddd5eae795da48f46edae274a431cbc

commit r12-6337-g1f759dbdcddd5eae795da48f46edae274a431cbc
Author: liuhongt <hongtao.liu@intel.com>
Date:   Wed Jan 5 15:26:18 2022 +0800

    Optimize V16HF vector insert to element 0 for AVX2.
    
    gcc/ChangeLog:
    
            PR target/103753
            * config/i386/i386-expand.c (ix86_expand_vector_set): Not use
            gen_avx2_pblendph_1 when elt == 0.
            * config/i386/sse.md (avx2_pblendph): Rename to ..
            (avx2_pblend<ssemodesuffix>_1).. this, and extend to V16HI.
            (*avx2_pblendw): Rename to ..
            (*avx2_pblend<ssemodesuffix>): .. this, and extend to V16HF.
            (avx2_pblendw): Rename to ..
            (*avx2_pblend<ssemodesuffix>): .. this, and extend to V16HF.
            (blendsuf): Removed.
            (sse4_1_pblend<blendsuf>): Renamed to ..
            (sse4_1_pblend<ssemodesuffix>): .. this.
    
    gcc/testsuite/ChangeLog:
    
            * gcc.target/i386/pr103753.c: New test.

Diff:
---
 gcc/config/i386/i386-expand.c            |  5 ++--
 gcc/config/i386/sse.md                   | 48 +++++++++++++++-----------------
 gcc/testsuite/gcc.target/i386/pr103753.c | 17 +++++++++++
 3 files changed, 42 insertions(+), 28 deletions(-)

diff --git a/gcc/config/i386/i386-expand.c b/gcc/config/i386/i386-expand.c
index 9bd8e539d08..0d4ae5a87f9 100644
--- a/gcc/config/i386/i386-expand.c
+++ b/gcc/config/i386/i386-expand.c
@@ -16245,10 +16245,11 @@ ix86_expand_vector_set (bool mmx_ok, rtx target, rtx val, int elt)
       goto half;
 
     case E_V16HFmode:
-      if (TARGET_AVX2)
+      /* For ELT == 0, vec_setv8hf_0 can save 1 vpbroadcastw.  */
+      if (TARGET_AVX2 && elt != 0)
 	{
 	  mmode = SImode;
-	  gen_blendm = gen_avx2_pblendph;
+	  gen_blendm = gen_avx2_pblendph_1;
 	  blendm_const = true;
 	  break;
 	}
diff --git a/gcc/config/i386/sse.md b/gcc/config/i386/sse.md
index fa1d56ae3e3..6c1e94f23d6 100644
--- a/gcc/config/i386/sse.md
+++ b/gcc/config/i386/sse.md
@@ -21292,10 +21292,7 @@
 	  (lt:VI1_AVX2 (match_dup 3) (match_dup 4))] UNSPEC_BLENDV))]
   "operands[3] = gen_lowpart (<MODE>mode, operands[3]);")
 
-(define_mode_attr blendsuf
-  [(V8HI "w") (V8HF "ph")])
-
-(define_insn "sse4_1_pblend<blendsuf>"
+(define_insn "sse4_1_pblend<ssemodesuffix>"
   [(set (match_operand:V8_128 0 "register_operand" "=Yr,*x,x")
 	(vec_merge:V8_128
 	  (match_operand:V8_128 2 "vector_operand" "YrBm,*xBm,xm")
@@ -21314,11 +21311,11 @@
    (set_attr "mode" "TI")])
 
 ;; The builtin uses an 8-bit immediate.  Expand that.
-(define_expand "avx2_pblendw"
-  [(set (match_operand:V16HI 0 "register_operand")
-	(vec_merge:V16HI
-	  (match_operand:V16HI 2 "nonimmediate_operand")
-	  (match_operand:V16HI 1 "register_operand")
+(define_expand "avx2_pblend<ssemodesuffix>"
+  [(set (match_operand:V16_256 0 "register_operand")
+	(vec_merge:V16_256
+	  (match_operand:V16_256 2 "nonimmediate_operand")
+	  (match_operand:V16_256 1 "register_operand")
 	  (match_operand:SI 3 "const_0_to_255_operand")))]
   "TARGET_AVX2"
 {
@@ -21326,11 +21323,11 @@
   operands[3] = GEN_INT (val << 8 | val);
 })
 
-(define_expand "avx2_pblendph"
-  [(set (match_operand:V16HF 0 "register_operand")
-	(vec_merge:V16HF
-	  (match_operand:V16HF 2 "register_operand")
-	  (match_operand:V16HF 1 "register_operand")
+(define_expand "avx2_pblend<ssemodesuffix>_1"
+  [(set (match_operand:V16_256 0 "register_operand")
+	(vec_merge:V16_256
+	  (match_operand:V16_256 2 "register_operand")
+	  (match_operand:V16_256 1 "register_operand")
 	  (match_operand:SI 3 "const_int_operand")))]
   "TARGET_AVX2
   && !((INTVAL (operands[3]) & 0xff) && (INTVAL (operands[3]) & 0xff00))"
@@ -21340,7 +21337,7 @@
     emit_move_insn (operands[0], operands[1]);
   else
    {
-     rtx tmp = gen_reg_rtx (V16HImode);
+     rtx tmp = gen_reg_rtx (<MODE>mode);
      rtx blendw_idx, blendd_idx;
 
      if (mask & 0xff)
@@ -21353,13 +21350,12 @@
 	 blendw_idx = GEN_INT (mask >> 8 & 0xff);
 	 blendd_idx = GEN_INT (240);
        }
-     operands[1] = lowpart_subreg (V16HImode, operands[1], V16HFmode);
-     operands[2] = lowpart_subreg (V16HImode, operands[2], V16HFmode);
-     emit_insn (gen_avx2_pblendw (tmp, operands[1], operands[2], blendw_idx));
+     emit_insn (gen_avx2_pblend<ssemodesuffix> (tmp, operands[1],
+						operands[2], blendw_idx));
 
-     operands[0] = lowpart_subreg (V8SImode, operands[0], V16HFmode);
-     tmp = lowpart_subreg (V8SImode, tmp, V16HImode);
-     operands[1] = lowpart_subreg (V8SImode, operands[1], V16HImode);
+     operands[0] = lowpart_subreg (V8SImode, operands[0], <MODE>mode);
+     tmp = lowpart_subreg (V8SImode, tmp, <MODE>mode);
+     operands[1] = lowpart_subreg (V8SImode, operands[1], <MODE>mode);
      emit_insn (gen_avx2_pblenddv8si (operands[0], operands[1],
 				      tmp, blendd_idx));
   }
@@ -21367,11 +21363,11 @@
   DONE;
 })
 
-(define_insn "*avx2_pblendw"
-  [(set (match_operand:V16HI 0 "register_operand" "=x")
-	(vec_merge:V16HI
-	  (match_operand:V16HI 2 "nonimmediate_operand" "xm")
-	  (match_operand:V16HI 1 "register_operand" "x")
+(define_insn "*avx2_pblend<ssemodesuffix>"
+  [(set (match_operand:V16_256 0 "register_operand" "=x")
+	(vec_merge:V16_256
+	  (match_operand:V16_256 2 "nonimmediate_operand" "xm")
+	  (match_operand:V16_256 1 "register_operand" "x")
 	  (match_operand:SI 3 "avx2_pblendw_operand" "n")))]
   "TARGET_AVX2"
 {
diff --git a/gcc/testsuite/gcc.target/i386/pr103753.c b/gcc/testsuite/gcc.target/i386/pr103753.c
new file mode 100644
index 00000000000..4b2b3e46d8b
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr103753.c
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-options "-mavx2 -mno-avx512f -O2" } */
+/* { dg-final { scan-assembler-not "vpbroadcastw" } } */
+
+typedef _Float16 __v16hf __attribute__ ((__vector_size__ (32)));
+
+__v16hf foo (_Float16 x)
+{
+  return (__v16hf) { x, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f };
+}
+
+typedef short __v16hi __attribute__ ((__vector_size__ (32)));
+
+__v16hi bar (short x)
+{
+  return (__v16hi) { x, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+}