[PATCH,picochip] More conservative settings for fconseve-stack

[Hariharan <hariharans at picochip dot com>]

Hi,
This patch changes the settings for flag-conserve-stack on picochip to 
be more conservative.

Committed to mainline.

Regards
Hari

ChangeLog:
        * config/picochip/picochip.c (flag_conserve_stack): set
        PARAM_LARGE_STACK_FRAME and PARAM_STACK_FRAME_GROWTH to zero
        under fconserve-stack. Reduce call-overhead used by inliner.

Patch:

Index: gcc/config/picochip/picochip.c
===================================================================
--- gcc/config/picochip/picochip.c      (revision 143783)
+++ gcc/config/picochip/picochip.c      (working copy)
@@ -50,6 +50,7 @@ along with GCC; see the file COPYING3.
 #include "target-def.h"
 #include "langhooks.h"
 #include "reload.h"
+#include "params.h"

 #include "picochip-protos.h"

@@ -303,6 +304,16 @@ picochip_return_in_memory(const_tree typ
 void
 picochip_override_options (void)
 {
+  /* If we are optimizing for stack, dont let inliner to inline functions
+     that could potentially increase stack size.*/
+   if (flag_conserve_stack)
+   {
+     PARAM_VALUE (PARAM_LARGE_STACK_FRAME) = 0;
+     PARAM_VALUE (PARAM_STACK_FRAME_GROWTH) = 0;
+   }
+   /* The function call overhead on picochip is not very high. Let the
+      inliner know so its heuristics become more reasonable. */
+   PARAM_VALUE (PARAM_INLINE_CALL_COST) = 2;

   /* Turn off the elimination of unused types. The elaborator
      generates various interesting types to represent constants,