[PATCH 6/8] [i386] Add patterns and predicates foutline-msabi-xlouges

[Daniel Santos <daniel.santos@pobox.com>]

Adds the predicates save_multiple and restore_multiple to predicates.md,
which are used by following patterns in sse.md:

* save_multiple - insn that calls a save stub
* restore_multiple - call_insn that calls a save stub and returns to the
  function to allow a sibling call (which should typically offer better
  optimization than the restore stub as the tail call)
* restore_multiple_and_return - a jump_insn that returns from the
  function as a tail-call.
* restore_multiple_leave_return - like the above, but restores the frame
  pointer before returning.

Signed-off-by: Daniel Santos <daniel.santos@pobox.com>
---
 gcc/config/i386/predicates.md | 155 ++++++++++++++++++++++++++++++++++++++++++
 gcc/config/i386/sse.md        |  37 ++++++++++
 2 files changed, 192 insertions(+)

diff --git a/gcc/config/i386/predicates.md b/gcc/config/i386/predicates.md
index 8f250a2e720..36fe8abc3f4 100644
--- a/gcc/config/i386/predicates.md
+++ b/gcc/config/i386/predicates.md
@@ -1657,3 +1657,158 @@
   (ior (match_operand 0 "register_operand")
        (and (match_code "const_int")
 	    (match_test "op == constm1_rtx"))))
+
+;; Return true if:
+;; 1. first op is a symbol reference,
+;; 2. >= 13 operands, and
+;; 3. operands 2 to end is one of:
+;;   a. save a register to a memory location, or
+;;   b. restore stack pointer.
+(define_predicate "save_multiple"
+  (match_code "parallel")
+{
+  const unsigned nregs = XVECLEN (op, 0);
+  rtx head = XVECEXP (op, 0, 0);
+  unsigned i;
+
+  if (GET_CODE (head) != USE)
+    return false;
+  else
+    {
+      rtx op0 = XEXP (head, 0);
+      if (op0 == NULL_RTX || GET_CODE (op0) != SYMBOL_REF)
+	return false;
+    }
+
+  if (nregs < 13)
+    return false;
+
+  for (i = 2; i < nregs; i++)
+    {
+      rtx e, src, dest;
+
+      e = XVECEXP (op, 0, i);
+
+      switch (GET_CODE (e))
+	{
+	  case SET:
+	    src  = SET_SRC (e);
+	    dest = SET_DEST (e);
+
+	    /* storing a register to memory.  */
+	    if (GET_CODE (src) == REG && GET_CODE (dest) == MEM)
+	      {
+		rtx addr = XEXP (dest, 0);
+
+		/* Good if dest address is in RAX.  */
+		if (GET_CODE (addr) == REG
+		    && REGNO (addr) == AX_REG)
+		  continue;
+
+		/* Good if dest address is offset of RAX.  */
+		if (GET_CODE (addr) == PLUS
+		    && GET_CODE (XEXP (addr, 0)) == REG
+		    && REGNO (XEXP (addr, 0)) == AX_REG)
+		  continue;
+	      }
+	    break;
+
+	  default:
+	    break;
+	}
+	return false;
+    }
+  return true;
+})
+
+;; Return true if:
+;; * first op is (return) or a a use (symbol reference),
+;; * >= 14 operands, and
+;; * operands 2 to end are one of:
+;;   - restoring a register from a memory location that's an offset of RSI.
+;;   - clobbering a reg
+;;   - adjusting SP
+(define_predicate "restore_multiple"
+  (match_code "parallel")
+{
+  const unsigned nregs = XVECLEN (op, 0);
+  rtx head = XVECEXP (op, 0, 0);
+  unsigned i;
+
+  switch (GET_CODE (head))
+    {
+      case RETURN:
+	i = 3;
+	break;
+
+      case USE:
+      {
+	rtx op0 = XEXP (head, 0);
+
+	if (op0 == NULL_RTX || GET_CODE (op0) != SYMBOL_REF)
+	  return false;
+
+	i = 1;
+	break;
+      }
+
+      default:
+	return false;
+    }
+
+  if (nregs < i + 12)
+    return false;
+
+  for (; i < nregs; i++)
+    {
+      rtx e, src, dest;
+
+      e = XVECEXP (op, 0, i);
+
+      switch (GET_CODE (e))
+	{
+	  case CLOBBER:
+	    continue;
+
+	  case SET:
+	    src  = SET_SRC (e);
+	    dest = SET_DEST (e);
+
+	    /* Restoring a register from memory.  */
+	    if (GET_CODE (src) == MEM && GET_CODE (dest) == REG)
+	      {
+		rtx addr = XEXP (src, 0);
+
+		/* Good if src address is in RSI.  */
+		if (GET_CODE (addr) == REG
+		    && REGNO (addr) == SI_REG)
+		  continue;
+
+		/* Good if src address is offset of RSI.  */
+		if (GET_CODE (addr) == PLUS
+		    && GET_CODE (XEXP (addr, 0)) == REG
+		    && REGNO (XEXP (addr, 0)) == SI_REG)
+		  continue;
+
+		/* Good if adjusting stack pointer.  */
+		if (GET_CODE (dest) == REG
+		    && REGNO (dest) == SP_REG
+		    && GET_CODE (src) == PLUS
+		    && GET_CODE (XEXP (src, 0)) == REG
+		    && REGNO (XEXP (src, 0)) == SP_REG)
+		  continue;
+	      }
+
+	    /* Restoring stack pointer from another register.  */
+	    if (GET_CODE (dest) == REG && REGNO (dest) == SP_REG
+		&& GET_CODE (src) == REG)
+	      continue;
+	    break;
+
+	  default:
+	    break;
+	}
+	return false;
+    }
+  return true;
+})
diff --git a/gcc/config/i386/sse.md b/gcc/config/i386/sse.md
index a19c8f2bc2e..b9db729c427 100644
--- a/gcc/config/i386/sse.md
+++ b/gcc/config/i386/sse.md
@@ -19885,3 +19885,40 @@
           (match_operand:VI48_512 1 "nonimmediate_operand" "vm")))]
   "TARGET_AVX512VPOPCNTDQ"
   "vpopcnt<ssemodesuffix>\t{%1, %0<mask_operand2>|%0<mask_operand2>, %1}")
+
+;; Save multiple registers out-of-line.
+(define_insn "save_multiple<mode>"
+  [(match_parallel 0 "save_multiple"
+    [(use (match_operand:P 1 "symbol_operand"))
+     (const_int 0)
+    ])]
+  "TARGET_SSE && TARGET_64BIT"
+  "call\t%P1")
+
+;; Restore multiple registers out-of-line.
+(define_insn "restore_multiple<mode>"
+  [(match_parallel 0 "restore_multiple"
+    [(use (match_operand:P 1 "symbol_operand"))])]
+  "TARGET_SSE && TARGET_64BIT"
+  "call\t%P1")
+
+;; Restore multiple registers out-of-line and return.
+(define_insn "restore_multiple_and_return<mode>"
+  [(match_parallel 0 "restore_multiple"
+    [(return)
+     (use (match_operand:P 1 "symbol_operand"))
+     (const_int 0)
+    ])]
+  "TARGET_SSE && TARGET_64BIT"
+  "jmp\t%P1")
+
+;; Restore multiple registers out-of-line when hard frame pointer is used,
+;; perform the leave operation prior to returning (from the function).
+(define_insn "restore_multiple_leave_return<mode>"
+  [(match_parallel 0 "restore_multiple"
+    [(return)
+     (use (match_operand:P 1 "symbol_operand"))
+     (const_int 1)
+    ])]
+  "TARGET_SSE && TARGET_64BIT"
+  "jmp\t%P1")
-- 
2.11.0