Fix inefficient vector constructor.

Changelog
gcc/
	PR target/92295
	* config/i386/i386-expand.c (ix86_expand_vector_init_concat)
	Enhance ix86_expand_vector_init_concat.

gcc/testsuite
	* gcc.target/i386/pr92295.c: New test.

From-SVN: r277946

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e723121b8ccb7bb7bb65168a73430fc6dd422cc3..9a33aa1ebe38237c498cc5a0a639d2ffac43c12f 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2019-11-08  Hongtao Liu  <Hongtao.liu@intel.com>
+
+       PR target/92295
+       * config/i386/i386-expand.c (ix86_expand_vector_init_concat)
+       Enhance ix86_expand_vector_init_concat.
+
 2019-11-08  Joseph Myers  <joseph@codesourcery.com>
 
        * doc/invoke.texi (-Wold-style-definition): Document () not being

diff --git a/gcc/config/i386/i386-expand.c b/gcc/config/i386/i386-expand.c
index 6d3d14c37dd6e22f718365ee01cb927c04bfec6c..be040a1bc3e9c3c8d29e7a2bb198e06579058b42 100644 (file)
--- a/gcc/config/i386/i386-expand.c
+++ b/gcc/config/i386/i386-expand.c
@@ -13654,8 +13654,8 @@ static void
 ix86_expand_vector_init_concat (machine_mode mode,
                                rtx target, rtx *ops, int n)
 {
-  machine_mode cmode, hmode = VOIDmode, gmode = VOIDmode;
-  rtx first[16], second[8], third[4];
+  machine_mode half_mode = VOIDmode;
+  rtx half[2];
   rtvec v;
   int i, j;
 
@@ -13665,55 +13665,55 @@ ix86_expand_vector_init_concat (machine_mode mode,
       switch (mode)
        {
        case E_V16SImode:
-         cmode = V8SImode;
+         half_mode = V8SImode;
          break;
        case E_V16SFmode:
-         cmode = V8SFmode;
+         half_mode = V8SFmode;
          break;
        case E_V8DImode:
-         cmode = V4DImode;
+         half_mode = V4DImode;
          break;
        case E_V8DFmode:
-         cmode = V4DFmode;
+         half_mode = V4DFmode;
          break;
        case E_V8SImode:
-         cmode = V4SImode;
+         half_mode = V4SImode;
          break;
        case E_V8SFmode:
-         cmode = V4SFmode;
+         half_mode = V4SFmode;
          break;
        case E_V4DImode:
-         cmode = V2DImode;
+         half_mode = V2DImode;
          break;
        case E_V4DFmode:
-         cmode = V2DFmode;
+         half_mode = V2DFmode;
          break;
        case E_V4SImode:
-         cmode = V2SImode;
+         half_mode = V2SImode;
          break;
        case E_V4SFmode:
-         cmode = V2SFmode;
+         half_mode = V2SFmode;
          break;
        case E_V2DImode:
-         cmode = DImode;
+         half_mode = DImode;
          break;
        case E_V2SImode:
-         cmode = SImode;
+         half_mode = SImode;
          break;
        case E_V2DFmode:
-         cmode = DFmode;
+         half_mode = DFmode;
          break;
        case E_V2SFmode:
-         cmode = SFmode;
+         half_mode = SFmode;
          break;
        default:
          gcc_unreachable ();
        }
 
-      if (!register_operand (ops[1], cmode))
-       ops[1] = force_reg (cmode, ops[1]);
-      if (!register_operand (ops[0], cmode))
-       ops[0] = force_reg (cmode, ops[0]);
+      if (!register_operand (ops[1], half_mode))
+       ops[1] = force_reg (half_mode, ops[1]);
+      if (!register_operand (ops[0], half_mode))
+       ops[0] = force_reg (half_mode, ops[0]);
       emit_insn (gen_rtx_SET (target, gen_rtx_VEC_CONCAT (mode, ops[0],
                                                          ops[1])));
       break;
@@ -13722,16 +13722,16 @@ ix86_expand_vector_init_concat (machine_mode mode,
       switch (mode)
        {
        case E_V4DImode:
-         cmode = V2DImode;
+         half_mode = V2DImode;
          break;
        case E_V4DFmode:
-         cmode = V2DFmode;
+         half_mode = V2DFmode;
          break;
        case E_V4SImode:
-         cmode = V2SImode;
+         half_mode = V2SImode;
          break;
        case E_V4SFmode:
-         cmode = V2SFmode;
+         half_mode = V2SFmode;
          break;
        default:
          gcc_unreachable ();
@@ -13742,20 +13742,16 @@ ix86_expand_vector_init_concat (machine_mode mode,
       switch (mode)
        {
        case E_V8DImode:
-         cmode = V2DImode;
-         hmode = V4DImode;
+         half_mode = V4DImode;
          break;
        case E_V8DFmode:
-         cmode = V2DFmode;
-         hmode = V4DFmode;
+         half_mode = V4DFmode;
          break;
        case E_V8SImode:
-         cmode = V2SImode;
-         hmode = V4SImode;
+         half_mode = V4SImode;
          break;
        case E_V8SFmode:
-         cmode = V2SFmode;
-         hmode = V4SFmode;
+         half_mode = V4SFmode;
          break;
        default:
          gcc_unreachable ();
@@ -13766,14 +13762,10 @@ ix86_expand_vector_init_concat (machine_mode mode,
       switch (mode)
        {
        case E_V16SImode:
-         cmode = V2SImode;
-         hmode = V4SImode;
-         gmode = V8SImode;
+         half_mode = V8SImode;
          break;
        case E_V16SFmode:
-         cmode = V2SFmode;
-         hmode = V4SFmode;
-         gmode = V8SFmode;
+         half_mode = V8SFmode;
          break;
        default:
          gcc_unreachable ();
@@ -13783,50 +13775,32 @@ ix86_expand_vector_init_concat (machine_mode mode,
 half:
       /* FIXME: We process inputs backward to help RA.  PR 36222.  */
       i = n - 1;
-      j = (n >> 1) - 1;
-      for (; i > 0; i -= 2, j--)
-       {
-         first[j] = gen_reg_rtx (cmode);
-         v = gen_rtvec (2, ops[i - 1], ops[i]);
-         ix86_expand_vector_init (false, first[j],
-                                  gen_rtx_PARALLEL (cmode, v));
-       }
-
-      n >>= 1;
-      if (n > 4)
-       {
-         gcc_assert (hmode != VOIDmode);
-         gcc_assert (gmode != VOIDmode);
-         for (i = j = 0; i < n; i += 2, j++)
-           {
-             second[j] = gen_reg_rtx (hmode);
-             ix86_expand_vector_init_concat (hmode, second [j],
-                                             &first [i], 2);
-           }
-         n >>= 1;
-         for (i = j = 0; i < n; i += 2, j++)
-           {
-             third[j] = gen_reg_rtx (gmode);
-             ix86_expand_vector_init_concat (gmode, third[j],
-                                             &second[i], 2);
-           }
-         n >>= 1;
-         ix86_expand_vector_init_concat (mode, target, third, n);
-       }
-      else if (n > 2)
+      for (j = 1; j != -1; j--)
        {
-         gcc_assert (hmode != VOIDmode);
-         for (i = j = 0; i < n; i += 2, j++)
+         half[j] = gen_reg_rtx (half_mode);
+         switch (n >> 1)
            {
-             second[j] = gen_reg_rtx (hmode);
-             ix86_expand_vector_init_concat (hmode, second [j],
-                                             &first [i], 2);
+           case 2:
+             v = gen_rtvec (2, ops[i-1], ops[i]);
+             i -= 2;
+             break;
+           case 4:
+             v = gen_rtvec (4, ops[i-3], ops[i-2], ops[i-1], ops[i]);
+             i -= 4;
+             break;
+           case 8:
+             v = gen_rtvec (8, ops[i-7], ops[i-6], ops[i-5], ops[i-4],
+                            ops[i-3], ops[i-2], ops[i-1], ops[i]);
+             i -= 8;
+             break;
+           default:
+             gcc_unreachable ();
            }
-         n >>= 1;
-         ix86_expand_vector_init_concat (mode, target, second, n);
+         ix86_expand_vector_init (false, half[j],
+                                  gen_rtx_PARALLEL (half_mode, v));
        }
-      else
-       ix86_expand_vector_init_concat (mode, target, first, n);
+
+      ix86_expand_vector_init_concat (mode, target, half, 2);
       break;
 
     default:

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 459fd8907ad995dde36c2c8ad8444f76c2fa7d3d..dec89484145af067767df4b94e6ed5306428823e 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2019-11-08  Hongtao Liu  <hongtao.liu@intel.com>
+
+       * gcc.target/i386/pr92295.c: New test.
+
 2019-11-08  Joseph Myers  <joseph@codesourcery.com>
 
        * gcc.dg/c11-old-style-definition-1.c,

diff --git a/gcc/testsuite/gcc.target/i386/pr92295.c b/gcc/testsuite/gcc.target/i386/pr92295.c
new file mode 100644 (file)
index 0000000..179dc48
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr92295.c
@@ -0,0 +1,13 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -march=skylake-avx512" } */
+
+typedef int X __attribute__((vector_size (32)));
+
+X
+foo (int x, int z)
+{
+  X y = { x, x, x, x, z, z, z, z };
+  return y;
+}
+
+/* { dg-final { scan-assembler-times "vpbroadcast" "2" } } */