arm-protos.h (offset_ok_for_ldrd_strd): New declaration.

2012-10-22  Sameera Deshpande  <sameera.deshpande@arm.com>
	    Greta Yorsh  <Greta.Yorsh@arm.com>

        * config/arm/arm-protos.h (offset_ok_for_ldrd_strd): New
        declaration.
        (operands_ok_ldrd_strd): Likewise.
        * config/arm/arm.c (offset_ok_for_ldrd_strd): New function.
        (operands_ok_ldrd_strd): Likewise.
        * config/arm/arm.md (thumb2_ldrd, thumb2_ldrd_base): New patterns.
        (thumb2_ldrd_base_neg): Likewise.
        (thumb2_strd, thumb2_strd_base, thumb_strd_base_neg): Likewise.
        * predicates.md (ldrd_strd_offset_operand): New predicate.
        * config/arm/constraints.md (Do): New constraint.



Co-Authored-By: Greta Yorsh <greta.yorsh@arm.com>

From-SVN: r192678

gcc/ChangeLog

+2012-10-22  Sameera Deshpande  <sameera.deshpande@arm.com>
+	    Greta Yorsh  <Greta.Yorsh@arm.com>
+
+        * config/arm/arm-protos.h (offset_ok_for_ldrd_strd): New
+        declaration.
+        (operands_ok_ldrd_strd): Likewise.
+        * config/arm/arm.c (offset_ok_for_ldrd_strd): New function.
+        (operands_ok_ldrd_strd): Likewise.
+        * config/arm/arm.md (thumb2_ldrd, thumb2_ldrd_base): New patterns.
+        (thumb2_ldrd_base_neg): Likewise.
+        (thumb2_strd, thumb2_strd_base, thumb_strd_base_neg): Likewise.
+        * predicates.md (ldrd_strd_offset_operand): New predicate.
+        * config/arm/constraints.md (Do): New constraint.
+
 2012-10-22  Hans-Peter Nilsson  <hp@bitrange.com>
 
 	* config/mmix/mmix.md ("nonlocal_goto_receiver"): Refer to the

gcc/config/arm/arm-protos.h

@@ -116,6 +116,8 @@ extern bool gen_stm_seq (rtx *, int);
 extern bool gen_const_stm_seq (rtx *, int);
 extern rtx arm_gen_load_multiple (int *, int, rtx, int, rtx, HOST_WIDE_INT *);
 extern rtx arm_gen_store_multiple (int *, int, rtx, int, rtx, HOST_WIDE_INT *);
+extern bool offset_ok_for_ldrd_strd (HOST_WIDE_INT);
+extern bool operands_ok_ldrd_strd (rtx, rtx, rtx, HOST_WIDE_INT, bool, bool);
 extern int arm_gen_movmemqi (rtx *);
 extern enum machine_mode arm_select_cc_mode (RTX_CODE, rtx, rtx);
 extern enum machine_mode arm_select_dominance_cc_mode (rtx, rtx,

gcc/config/arm/arm.c

@@ -12193,6 +12193,75 @@ arm_pad_reg_upward (enum machine_mode mode,
   return !BYTES_BIG_ENDIAN;
 }
 
+/* Returns true iff OFFSET is valid for use in an LDRD/STRD instruction,
+   assuming that the address in the base register is word aligned.  */
+bool
+offset_ok_for_ldrd_strd (HOST_WIDE_INT offset)
+{
+  HOST_WIDE_INT max_offset;
+
+  /* Offset must be a multiple of 4 in Thumb mode.  */
+  if (TARGET_THUMB2 && ((offset & 3) != 0))
+    return false;
+
+  if (TARGET_THUMB2)
+    max_offset = 1020;
+  else if (TARGET_ARM)
+    max_offset = 255;
+  else
+    gcc_unreachable ();
+
+  return ((offset <= max_offset) && (offset >= -max_offset));
+}
+
+/* Checks whether the operands are valid for use in an LDRD/STRD instruction.
+   Assumes that RT, RT2, and RN are REG.  This is guaranteed by the patterns.
+   Assumes that the address in the base register RN is word aligned.  Pattern
+   guarantees that both memory accesses use the same base register,
+   the offsets are constants within the range, and the gap between the offsets is 4.
+   If preload complete then check that registers are legal.  WBACK indicates whether
+   address is updated.  LOAD indicates whether memory access is load or store.  */
+bool
+operands_ok_ldrd_strd (rtx rt, rtx rt2, rtx rn, HOST_WIDE_INT offset,
+                       bool wback, bool load)
+{
+  unsigned int t, t2, n;
+
+  if (!reload_completed)
+    return true;
+
+  if (!offset_ok_for_ldrd_strd (offset))
+    return false;
+
+  t = REGNO (rt);
+  t2 = REGNO (rt2);
+  n = REGNO (rn);
+
+  if ((TARGET_THUMB2)
+      && ((wback && (n == t || n == t2))
+          || (t == SP_REGNUM)
+          || (t == PC_REGNUM)
+          || (t2 == SP_REGNUM)
+          || (t2 == PC_REGNUM)
+          || (!load && (n == PC_REGNUM))
+          || (load && (t == t2))
+          /* Triggers Cortex-M3 LDRD errata.  */
+          || (!wback && load && fix_cm3_ldrd && (n == t))))
+    return false;
+
+  if ((TARGET_ARM)
+      && ((wback && (n == t || n == t2))
+          || (t2 == PC_REGNUM)
+          || (t % 2 != 0)   /* First destination register is not even.  */
+          || (t2 != t + 1)
+          /* PC can be used as base register (for offset addressing only),
+             but it is depricated.  */
+          || (n == PC_REGNUM)))
+    return false;
+
+  return true;
+}
+
 
 /* Print a symbolic form of X to the debug file, F.  */
 static void

gcc/config/arm/arm.md

@@ -11511,6 +11511,99 @@
 ""
 )
 
+;; Patterns for LDRD/STRD in Thumb2 mode
+
+(define_insn "*thumb2_ldrd"
+  [(set (match_operand:SI 0 "s_register_operand" "=r")
+        (mem:SI (plus:SI (match_operand:SI 1 "s_register_operand" "rk")
+                         (match_operand:SI 2 "ldrd_strd_offset_operand" "Do"))))
+   (set (match_operand:SI 3 "s_register_operand" "=r")
+        (mem:SI (plus:SI (match_dup 1)
+                         (match_operand:SI 4 "const_int_operand" ""))))]
+  "TARGET_LDRD && TARGET_THUMB2 && reload_completed
+     && current_tune->prefer_ldrd_strd
+     && ((INTVAL (operands[2]) + 4) == INTVAL (operands[4]))
+     && (operands_ok_ldrd_strd (operands[0], operands[3],
+                                  operands[1], INTVAL (operands[2]),
+                                  false, true))"
+  "ldrd%?\t%0, %3, [%1, %2]"
+  [(set_attr "type" "load2")
+   (set_attr "predicable" "yes")])
+
+(define_insn "*thumb2_ldrd_base"
+  [(set (match_operand:SI 0 "s_register_operand" "=r")
+        (mem:SI (match_operand:SI 1 "s_register_operand" "rk")))
+   (set (match_operand:SI 2 "s_register_operand" "=r")
+        (mem:SI (plus:SI (match_dup 1)
+                         (const_int 4))))]
+  "TARGET_LDRD && TARGET_THUMB2 && reload_completed
+     && current_tune->prefer_ldrd_strd
+     && (operands_ok_ldrd_strd (operands[0], operands[2],
+                                  operands[1], 0, false, true))"
+  "ldrd%?\t%0, %2, [%1]"
+  [(set_attr "type" "load2")
+   (set_attr "predicable" "yes")])
+
+(define_insn "*thumb2_ldrd_base_neg"
+  [(set (match_operand:SI 0 "s_register_operand" "=r")
+	(mem:SI (plus:SI (match_operand:SI 1 "s_register_operand" "rk")
+                         (const_int -4))))
+   (set (match_operand:SI 2 "s_register_operand" "=r")
+        (mem:SI (match_dup 1)))]
+  "TARGET_LDRD && TARGET_THUMB2 && reload_completed
+     && current_tune->prefer_ldrd_strd
+     && (operands_ok_ldrd_strd (operands[0], operands[2],
+                                  operands[1], -4, false, true))"
+  "ldrd%?\t%0, %2, [%1, #-4]"
+  [(set_attr "type" "load2")
+   (set_attr "predicable" "yes")])
+
+(define_insn "*thumb2_strd"
+  [(set (mem:SI (plus:SI (match_operand:SI 0 "s_register_operand" "rk")
+                         (match_operand:SI 1 "ldrd_strd_offset_operand" "Do")))
+        (match_operand:SI 2 "s_register_operand" "r"))
+   (set (mem:SI (plus:SI (match_dup 0)
+                         (match_operand:SI 3 "const_int_operand" "")))
+        (match_operand:SI 4 "s_register_operand" "r"))]
+  "TARGET_LDRD && TARGET_THUMB2 && reload_completed
+     && current_tune->prefer_ldrd_strd
+     && ((INTVAL (operands[1]) + 4) == INTVAL (operands[3]))
+     && (operands_ok_ldrd_strd (operands[2], operands[4],
+                                  operands[0], INTVAL (operands[1]),
+                                  false, false))"
+  "strd%?\t%2, %4, [%0, %1]"
+  [(set_attr "type" "store2")
+   (set_attr "predicable" "yes")])
+
+(define_insn "*thumb2_strd_base"
+  [(set (mem:SI (match_operand:SI 0 "s_register_operand" "rk"))
+        (match_operand:SI 1 "s_register_operand" "r"))
+   (set (mem:SI (plus:SI (match_dup 0)
+                         (const_int 4)))
+        (match_operand:SI 2 "s_register_operand" "r"))]
+  "TARGET_LDRD && TARGET_THUMB2 && reload_completed
+     && current_tune->prefer_ldrd_strd
+     && (operands_ok_ldrd_strd (operands[1], operands[2],
+                                  operands[0], 0, false, false))"
+  "strd%?\t%1, %2, [%0]"
+  [(set_attr "type" "store2")
+   (set_attr "predicable" "yes")])
+
+(define_insn "*thumb2_strd_base_neg"
+  [(set (mem:SI (plus:SI (match_operand:SI 0 "s_register_operand" "rk")
+                         (const_int -4)))
+        (match_operand:SI 1 "s_register_operand" "r"))
+   (set (mem:SI (match_dup 0))
+        (match_operand:SI 2 "s_register_operand" "r"))]
+  "TARGET_LDRD && TARGET_THUMB2 && reload_completed
+     && current_tune->prefer_ldrd_strd
+     && (operands_ok_ldrd_strd (operands[1], operands[2],
+                                  operands[0], -4, false, false))"
+  "strd%?\t%1, %2, [%0, #-4]"
+  [(set_attr "type" "store2")
+   (set_attr "predicable" "yes")])
+
+
 ;; Load the load/store multiple patterns
 (include "ldmstm.md")
 

gcc/config/arm/constraints.md

@@ -31,7 +31,7 @@
 ;; 'H' was previously used for FPA.
 
 ;; The following multi-letter normal constraints have been used:
-;; in ARM/Thumb-2 state: Da, Db, Dc, Dd, Dn, Dl, DL, Dv, Dy, Di, Dt, Dz
+;; in ARM/Thumb-2 state: Da, Db, Dc, Dd, Dn, Dl, DL, Do, Dv, Dy, Di, Dt, Dz
 ;; in Thumb-1 state: Pa, Pb, Pc, Pd, Pe
 ;; in Thumb-2 state: Pj, PJ, Ps, Pt, Pu, Pv, Pw, Px, Py
 
@@ -279,6 +279,12 @@
       (match_test "TARGET_32BIT
 		   && imm_for_neon_inv_logic_operand (op, GET_MODE (op))")))
 
+(define_constraint "Do"
+ "@internal
+  In ARM/Thumb2 state valid offset for an ldrd/strd instruction."
+ (and (match_code "const_int")
+      (match_test "TARGET_LDRD && offset_ok_for_ldrd_strd (ival)")))
+
 (define_constraint "Dv"
  "@internal
   In ARM/Thumb-2 state a const_double which can be used with a VFP fconsts

gcc/config/arm/predicates.md

@@ -137,6 +137,10 @@
        (match_test "((unsigned HOST_WIDE_INT) INTVAL (op)) <= GET_MODE_BITSIZE (mode)
 	&& ((unsigned HOST_WIDE_INT) INTVAL (op)) > 0")))
 
+(define_predicate "ldrd_strd_offset_operand"
+  (and (match_operand 0 "const_int_operand")
+       (match_test "TARGET_LDRD && offset_ok_for_ldrd_strd (INTVAL (op))")))
+
 (define_predicate "arm_add_operand"
   (ior (match_operand 0 "arm_rhs_operand")
        (match_operand 0 "arm_neg_immediate_operand")))