arm.h (CONDITIONAL_REGISTER_USAGE): If flag_pic, never use PIC_OFFSET_TABLE_REGNUM for general alloaction.

* arm.h (CONDITIONAL_REGISTER_USAGE): If flag_pic, never use
PIC_OFFSET_TABLE_REGNUM for general alloaction.
(INITIAL_ELIMINATION_OFFSET): Count the fact that the PIC register
must be stacked if it is used for PIC accesses.
* arm.c (use_return_insn): Handle PIC register specially.
(output_return_instruction): Likewise.
(output_func_{prologue,epilogue}): Likewise.
(output_expand_prologue): Likewise.

From-SVN: r27605

3 files changed, 47 insertions, 9 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 46f9d17..6d09229 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,14 @@
+Sat Jun 19 05:25:05 1999  Richard Earnshaw (rearnsha@arm.com)
+
+	* arm.h (CONDITIONAL_REGISTER_USAGE): If flag_pic, never use
+	PIC_OFFSET_TABLE_REGNUM for general alloaction.
+	(INITIAL_ELIMINATION_OFFSET): Count the fact that the PIC register
+	must be stacked if it is used for PIC accesses.
+	* arm.c (use_return_insn): Handle PIC register specially.
+	(output_return_instruction): Likewise.
+	(output_func_{prologue,epilogue}): Likewise.
+	(output_expand_prologue): Likewise.
+
 Fri Jun 18 23:47:06 1999  David Edelsohn  <edelsohn@gnu.org>
 
 	* rs6000.c (find_addr_reg): New function.
diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index ae9572b..e214993 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -585,9 +585,14 @@ use_return_insn (iscond)
     return 0;
   if ((iscond && arm_is_strong)
       || TARGET_THUMB_INTERWORK)
-    for (regno = 0; regno < 16; regno++)
-      if (regs_ever_live[regno] && ! call_used_regs[regno])
+    {
+      for (regno = 0; regno < 16; regno++)
+	if (regs_ever_live[regno] && ! call_used_regs[regno])
+	  return 0;
+
+      if (flag_pic && regs_ever_live[PIC_OFFSET_TABLE_REGNUM])
 	return 0;
+    }
       
   /* Can't be done if any of the FPU regs are pushed, since this also
      requires an insn */
@@ -5321,6 +5326,9 @@ output_return_instruction (operand, really_return, reverse)
     if (regs_ever_live[reg] && ! call_used_regs[reg])
       live_regs++;
 
+  if (flag_pic && regs_ever_live[PIC_OFFSET_TABLE_REGNUM])
+    live_regs++;
+
   if (live_regs || (regs_ever_live[14] && ! lr_save_eliminated))
     live_regs++;
 
@@ -5340,7 +5348,9 @@ output_return_instruction (operand, really_return, reverse)
 		reverse ? "ldm%?%D0fd\t%|sp!, {" : "ldm%?%d0fd\t%|sp!, {");
 
       for (reg = 0; reg <= 10; reg++)
-        if (regs_ever_live[reg] && ! call_used_regs[reg])
+        if (regs_ever_live[reg] 
+	    && (! call_used_regs[reg]
+		|| (flag_pic && reg == PIC_OFFSET_TABLE_REGNUM)))
           {
 	    strcat (instr, "%|");
             strcat (instr, reg_names[reg]);
@@ -5500,6 +5510,9 @@ output_func_prologue (f, frame_size)
     if (regs_ever_live[reg] && ! call_used_regs[reg])
       live_regs_mask |= (1 << reg);
 
+  if (flag_pic && regs_ever_live[PIC_OFFSET_TABLE_REGNUM])
+    live_regs_mask |= (1 << PIC_OFFSET_TABLE_REGNUM);
+
   if (frame_pointer_needed)
     live_regs_mask |= 0xD800;
   else if (regs_ever_live[14])
@@ -5576,6 +5589,12 @@ output_func_epilogue (f, frame_size)
 	floats_offset += 4;
       }
 
+  if (flag_pic && regs_ever_live[PIC_OFFSET_TABLE_REGNUM])
+    {
+      live_regs_mask |= (1 << PIC_OFFSET_TABLE_REGNUM);
+      floats_offset += 4;
+    }
+
   if (frame_pointer_needed)
     {
       if (arm_fpu_arch == FP_SOFT2)
@@ -5836,12 +5855,17 @@ arm_expand_prologue ()
     store_arg_regs = 1;
 
   if (! volatile_func)
-    for (reg = 0; reg <= 10; reg++)
-      if (regs_ever_live[reg] && ! call_used_regs[reg])
-	live_regs_mask |= 1 << reg;
+    {
+      for (reg = 0; reg <= 10; reg++)
+	if (regs_ever_live[reg] && ! call_used_regs[reg])
+	  live_regs_mask |= 1 << reg;
+
+      if (flag_pic && regs_ever_live[PIC_OFFSET_TABLE_REGNUM])
+	live_regs_mask |= 1 << PIC_OFFSET_TABLE_REGNUM;
 
-  if (! volatile_func && regs_ever_live[14])
-    live_regs_mask |= 0x4000;
+      if (regs_ever_live[14])
+	live_regs_mask |= 0x4000;
+    }
 
   if (frame_pointer_needed)
     {
diff --git a/gcc/config/arm/arm.h b/gcc/config/arm/arm.h
index 87a141a..807340f 100644
--- a/gcc/config/arm/arm.h
+++ b/gcc/config/arm/arm.h
@@ -725,7 +725,7 @@ extern const char * structure_size_string;
   if (flag_pic)						\
     {							\
       fixed_regs[PIC_OFFSET_TABLE_REGNUM] = 1;		\
-      call_used_regs[PIC_OFFSET_TABLE_REGNUM] = 0;	\
+      call_used_regs[PIC_OFFSET_TABLE_REGNUM] = 1;	\
     }							\
   else if (TARGET_APCS_STACK)				\
     {							\
@@ -1262,6 +1262,9 @@ do {									\
           for (regno = 0; regno <= 10; regno++)				\
 	    if (regs_ever_live[regno] && ! call_used_regs[regno])	\
 	      saved_hard_reg = 1, offset += 4;				\
+	  /* PIC register is a fixed reg, so call_used_regs set.  */	\
+	  if (flag_pic && regs_ever_live[PIC_OFFSET_TABLE_REGNUM])	\
+	    saved_hard_reg = 1, offset += 4;				\
           for (regno = 16; regno <=23; regno++)				\
 	    if (regs_ever_live[regno] && ! call_used_regs[regno])	\
 	      offset += 12;						\