* config/pdp11/pdp11-protos.h (pdp11_initial_elimination_offset,

pdp11_regno_reg_class): New functions.
* config/pdp11/pdp11.md (define_constants): Add register numbers.
* config/pdp11/pdp11.c (pdp11_regno_reg_class,
pdp11_sp_frame_offset, pdp11_initial_elimination_offset): New
functions. 
* config/pdp11/pdp11.h (FIXED_REGISTERS, CALL_USED_REGISTERS): Add
frame pointer and argument pointer pseudo-registers.
(ARG_POINTER_REGNUM): Define.
(REG_CLASS_CONTENTS, REGNO_REG_CLASS): Add frame pointer and
argument pointer. 
(FIRST_PARM_OFFSET): Update for argument pointer.
(INITIAL_FRAME_POINTER_OFFSET): Delete.
(ELIMINABLE_REGS, INITIAL_ELIMINATION_OFFSET): New macros.
(REGNO_OK_FOR_BASE_P, REGNO_OK_FOR_INDEX_P, REGISTER_NAMES): Add
frame pointer and argument pointer. 

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@166978 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 67 insertions, 2 deletions

diff --git a/gcc/config/pdp11/pdp11.c b/gcc/config/pdp11/pdp11.c
index 760026df7d2..617a7f56080 100644
--- a/gcc/config/pdp11/pdp11.c
+++ b/gcc/config/pdp11/pdp11.c
@@ -300,7 +300,7 @@ pdp11_output_function_prologue (FILE *stream, HOST_WIDE_INT size)
 	asm_fprintf (stream, "\tsub $%#wo, sp\n", fsize);
 
     /* save CPU registers  */
-    for (regno = 0; regno <= PC_REGNUM; regno++)				
+    for (regno = R0_REGNUM; regno <= PC_REGNUM; regno++)				
       if (df_regs_ever_live_p (regno) && ! call_used_regs[regno])	
 	    if (! ((regno == FRAME_POINTER_REGNUM)			
 		   && frame_pointer_needed))				
@@ -379,7 +379,7 @@ pdp11_output_function_epilogue (FILE *stream, HOST_WIDE_INT size)
 	k = 2*j;
 	
 	/* change fp -> r5 due to the compile error on libgcc2.c */
-	for (i = PC_REGNUM ; i >= 0 ; i--)					
+	for (i = PC_REGNUM ; i >= R0_REGNUM ; i--)					
 	  if (df_regs_ever_live_p (i) && ! call_used_regs[i])		
 		fprintf(stream, "\tmov %#" HOST_WIDE_INT_PRINT "o(r5), %s\n",
 			(-fsize-2*j--)&0xffff, reg_names[i]);
@@ -1706,6 +1706,71 @@ pdp11_secondary_memory_needed (reg_class_t c1, reg_class_t c2,
   return (fromfloat != tofloat);
 }
 
+/* Return the class number of the smallest class containing
+   reg number REGNO.  */
+enum reg_class
+pdp11_regno_reg_class (int regno)
+{ 
+  if (regno == FRAME_POINTER_REGNUM || regno == ARG_POINTER_REGNUM)
+    return GENERAL_REGS;
+  else if (regno > AC3_REGNUM)
+    return NO_LOAD_FPU_REGS;
+  else if (regno >= AC0_REGNUM)
+    return LOAD_FPU_REGS;
+  else if (regno & 1)
+    return MUL_REGS;
+  else
+    return GENERAL_REGS;
+}
+
+
+static int
+pdp11_sp_frame_offset (void)
+{
+  int offset = 0, regno;
+  offset = get_frame_size();
+  for (regno = 0; regno <= PC_REGNUM; regno++)
+    if (df_regs_ever_live_p (regno) && ! call_used_regs[regno])
+      offset += 2;
+  for (regno = AC0_REGNUM; regno <= AC5_REGNUM; regno++)
+    if (df_regs_ever_live_p (regno) && ! call_used_regs[regno])
+      offset += 8;
+  
+  return offset;
+}   
+
+/* Return the offset between two registers, one to be eliminated, and the other
+   its replacement, at the start of a routine.  */
+
+int
+pdp11_initial_elimination_offset (int from, int to)
+{
+  int spoff;
+  
+  if (from == ARG_POINTER_REGNUM && to == HARD_FRAME_POINTER_REGNUM)
+    return 4;
+  else if (from == FRAME_POINTER_REGNUM
+	   && to == HARD_FRAME_POINTER_REGNUM)
+    return 0;
+  else
+    {
+      gcc_assert (to == STACK_POINTER_REGNUM);
+
+      /* Get the size of the register save area.  */
+      spoff = pdp11_sp_frame_offset ();
+      if (from == FRAME_POINTER_REGNUM)
+	return spoff;
+
+      gcc_assert (from == ARG_POINTER_REGNUM);
+
+      /* If there is a frame pointer, that is saved too.  */
+      if (frame_pointer_needed)
+	spoff += 2;
+      
+      /* Account for the saved PC in the function call.  */
+      return spoff + 2;
+    }
+}    
 
 /* A copy of output_addr_const modified for pdp11 expression syntax.
    output_addr_const also gets called for %cDIGIT and %nDIGIT, which we don't