arm.c (output_move_double): Prefer LDRD to LDM.

2008-03-12  Paul Brook  <paul@codesourcery.com>

	gcc/
	* config/arm/arm.c (output_move_double): Prefer LDRD to LDM.

From-SVN: r133160

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 94d21b541fee632ecea33389d7bc6c563a800fe1..d64295d7ce9c3853955908cefbef06a52a88706f 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,7 @@
+2008-03-12  Paul Brook  <paul@codesourcery.com>
+
+       * config/arm/arm.c (output_move_double): Prefer LDRD to LDM.
+
 2008-03-12  Paul Brook  <paul@codesourcery.com>
 
        * config/arm/thumb2.md: Extend peephole to cover 3-arg subs.

diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index 5f92e4649f4c72472f967d32bd81af6047b32e69..f3febf6c4192f24a1ac2d2af016902d40ba0903a 100644 (file)
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -9869,7 +9869,10 @@ output_move_double (rtx *operands)
       switch (GET_CODE (XEXP (operands[1], 0)))
        {
        case REG:
-         output_asm_insn ("ldm%(ia%)\t%m1, %M0", operands);
+         if (TARGET_LDRD)
+           output_asm_insn ("ldr%(d%)\t%0, [%m1]", operands);
+         else
+           output_asm_insn ("ldm%(ia%)\t%m1, %M0", operands);
          break;
 
        case PRE_INC:
@@ -9885,7 +9888,10 @@ output_move_double (rtx *operands)
          break;
 
        case POST_INC:
-         output_asm_insn ("ldm%(ia%)\t%m1!, %M0", operands);
+         if (TARGET_LDRD)
+           output_asm_insn ("ldr%(d%)\t%0, [%m1], #8", operands);
+         else
+           output_asm_insn ("ldm%(ia%)\t%m1!, %M0", operands);
          break;
 
        case POST_DEC:
@@ -9944,8 +9950,14 @@ output_move_double (rtx *operands)
 
        case LABEL_REF:
        case CONST:
+         /* We might be able to use ldrd %0, %1 here.  However the range is
+            different to ldr/adr, and it is broken on some ARMv7-M
+            implementations.  */
          output_asm_insn ("adr%?\t%0, %1", operands);
-         output_asm_insn ("ldm%(ia%)\t%0, %M0", operands);
+         if (TARGET_LDRD)
+           output_asm_insn ("ldr%(d%)\t%0, [%0]", operands);
+         else
+           output_asm_insn ("ldm%(ia%)\t%0, %M0", operands);
          break;
 
          /* ??? This needs checking for thumb2.  */
@@ -9959,7 +9971,7 @@ output_move_double (rtx *operands)
 
              if (GET_CODE (XEXP (operands[1], 0)) == PLUS)
                {
-                 if (GET_CODE (otherops[2]) == CONST_INT)
+                 if (GET_CODE (otherops[2]) == CONST_INT && !TARGET_LDRD)
                    {
                      switch ((int) INTVAL (otherops[2]))
                        {
@@ -10018,6 +10030,9 @@ output_move_double (rtx *operands)
              else
                output_asm_insn ("sub%?\t%0, %1, %2", otherops);
 
+             if (TARGET_LDRD)
+               return "ldr%(d%)\t%0, [%0]";
+
              return "ldm%(ia%)\t%0, %M0";
            }
          else
@@ -10046,7 +10061,10 @@ output_move_double (rtx *operands)
       switch (GET_CODE (XEXP (operands[0], 0)))
         {
        case REG:
-         output_asm_insn ("stm%(ia%)\t%m0, %M1", operands);
+         if (TARGET_LDRD)
+           output_asm_insn ("str%(d%)\t%1, [%m0]", operands);
+         else
+           output_asm_insn ("stm%(ia%)\t%m0, %M1", operands);
          break;
 
         case PRE_INC:
@@ -10062,7 +10080,10 @@ output_move_double (rtx *operands)
          break;
 
         case POST_INC:
-         output_asm_insn ("stm%(ia%)\t%m0!, %M1", operands);
+         if (TARGET_LDRD)
+           output_asm_insn ("str%(d%)\t%1, [%m0], #8", operands);
+         else
+           output_asm_insn ("stm%(ia%)\t%m0!, %M1", operands);
          break;
 
         case POST_DEC:
@@ -10106,7 +10127,7 @@ output_move_double (rtx *operands)
 
        case PLUS:
          otherops[2] = XEXP (XEXP (operands[0], 0), 1);
-         if (GET_CODE (otherops[2]) == CONST_INT)
+         if (GET_CODE (otherops[2]) == CONST_INT && !TARGET_LDRD)
            {
              switch ((int) INTVAL (XEXP (XEXP (operands[0], 0), 1)))
                {