Update i386 piecewise move and store

We can use TImode/OImode/XImode integers for piecewise move and store.
When vector register is used for piecewise move and store, we don't
increase stack_alignment_needed since vector register spill isn't
required for piecewise move and store.  Since stack_realign_needed is
set to true by checking stack_alignment_estimated set by pseudo vector
register usage, we also need to check stack_realign_needed to eliminate
frame pointer.

	* config/i386/i386.c (ix86_finalize_stack_realign_flags): Also
	check stack_realign_needed for stack realignment.
	(ix86_legitimate_constant_p): Always allow CONST_WIDE_INT smaller
	than the largest integer supported by vector register.
	* config/i386/i386.h (MOVE_MAX): Set to 64.
	(MOVE_MAX_PIECES): Set to bytes of the largest integer supported
	by vector register.
	(STORE_MAX_PIECES): New.

2 files changed, 39 insertions, 5 deletions

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 60aa992c68e..a07f9d56b82 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -13286,8 +13286,15 @@ ix86_finalize_stack_realign_flags (void)
   /* If the only reason for frame_pointer_needed is that we conservatively
      assumed stack realignment might be needed, but in the end nothing that
      needed the stack alignment had been spilled, clear frame_pointer_needed
-     and say we don't need stack realignment.  */
-  if (stack_realign
+     and say we don't need stack realignment.
+
+     When vector register is used for piecewise move and store, we don't
+     increase stack_alignment_needed as there is no register spill for
+     piecewise move and store.  Since stack_realign_needed is set to true
+     by checking stack_alignment_estimated which is updated by pseudo
+     vector register usage, we also need to check stack_realign_needed to
+     eliminate frame pointer.  */
+  if ((stack_realign || crtl->stack_realign_needed)
       && frame_pointer_needed
       && crtl->is_leaf
       && flag_omit_frame_pointer
@@ -15228,7 +15235,13 @@ ix86_legitimate_constant_p (machine_mode mode, rtx x)
 	  /* FALLTHRU */
 	case OImode:
 	case XImode:
-	  if (!standard_sse_constant_p (x, mode))
+	  if (!standard_sse_constant_p (x, mode)
+	      && GET_MODE_SIZE (TARGET_AVX512F
+				? XImode
+				: (TARGET_AVX
+				   ? OImode
+				   : (TARGET_SSE2
+				      ? TImode : DImode))) < GET_MODE_SIZE (mode))
 	    return false;
 	default:
 	  break;
diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
index 9b662648f7f..b8bd54a6728 100644
--- a/gcc/config/i386/i386.h
+++ b/gcc/config/i386/i386.h
@@ -1946,12 +1946,33 @@ typedef struct ix86_args {
 
 /* Max number of bytes we can move from memory to memory
    in one reasonably fast instruction.  */
-#define MOVE_MAX 16
+#define MOVE_MAX 64
 
 /* MOVE_MAX_PIECES is the number of bytes at a time which we can
    move efficiently, as opposed to  MOVE_MAX which is the maximum
    number of bytes we can move with a single instruction.  */
-#define MOVE_MAX_PIECES UNITS_PER_WORD
+#define MOVE_MAX_PIECES \
+  (TARGET_AVX512F \
+   ? 64 \
+   : (TARGET_AVX \
+      ? ((!TARGET_AVX256_SPLIT_UNALIGNED_LOAD \
+	  && !TARGET_AVX256_SPLIT_UNALIGNED_STORE) ? 32 : 16) \
+      : ((TARGET_SSE2 \
+	  && TARGET_SSE_UNALIGNED_LOAD_OPTIMAL \
+	  && TARGET_SSE_UNALIGNED_STORE_OPTIMAL) \
+	 ? 16 : UNITS_PER_WORD)))
+
+/* STORE_MAX_PIECES is the number of bytes at a time that we can
+   store efficiently.  */
+#define STORE_MAX_PIECES \
+  (TARGET_AVX512F \
+   ? 64 \
+   : (TARGET_AVX \
+      ? ((!TARGET_AVX256_SPLIT_UNALIGNED_STORE \
+	  && !TARGET_AVX256_SPLIT_UNALIGNED_STORE) ? 32 : 16) \
+      : ((TARGET_SSE2 \
+	  && TARGET_SSE_UNALIGNED_STORE_OPTIMAL) \
+	 ? 16 : UNITS_PER_WORD)))
 
 /* If a memory-to-memory move would take MOVE_RATIO or more simple
    move-instruction pairs, we will do a movmem or libcall instead.