[MIPS] Leave room for frame header on stack for MIPS arch

src/trusted/service_runtime/nacl_config.h

Index: src/trusted/service_runtime/nacl_config.h
diff --git a/src/trusted/service_runtime/nacl_config.h b/src/trusted/service_runtime/nacl_config.h
index c6309b8836258cc9dafb7ff7b5b2c69b9ef5eb0a..b554e4f0b04f518995eebef627bf5225e8886538 100644
--- a/src/trusted/service_runtime/nacl_config.h
+++ b/src/trusted/service_runtime/nacl_config.h
@@ -184,6 +184,7 @@
  * must do so here as well.
  */
 #  define NACL_STACK_ALIGN_MASK   (0xf)
+#  define NACL_STACK_ARG_SIZE     (0)
 #  define NACL_STACK_GETS_ARG     (1)
 #  define NACL_STACK_PAD_BELOW_ALIGN (4)
 #  define NACL_STACK_RED_ZONE     (0)
@@ -204,6 +205,7 @@
  * 3.2.2 discusses stack alignment.
  */
 #  define NACL_STACK_ALIGN_MASK   (0xf)
+#  define NACL_STACK_ARG_SIZE     (0)
 #  define NACL_STACK_GETS_ARG     (0)
 #  define NACL_STACK_PAD_BELOW_ALIGN (8)
 #  define NACL_STACK_RED_ZONE     (128)
@@ -239,6 +241,7 @@
  * performance of vector instructions, we increase this to 16.
  */
 # define NACL_STACK_ALIGN_MASK    (0xf)
+# define NACL_STACK_ARG_SIZE      (0)
 # define NACL_STACK_GETS_ARG      (0)
 # define NACL_STACK_PAD_BELOW_ALIGN (0)
 # define NACL_STACK_RED_ZONE      (0)
@@ -270,6 +273,11 @@
 # define NACL_USERRET_FIX           (-0x4)
 # define NACL_SYSARGS_FIX           (0)
 # define NACL_STACK_ALIGN_MASK      (0x7)
+/*
+ * The MIPS o32 ABI requires callers to reserve 16 bytes above the stack
+ * pointer, which the callee can spill arguments to.
+ */
+# define NACL_STACK_ARG_SIZE        (0x10)

[Mark Seaborn, 2013/03/07 16:07:53]

Maybe calls this "ARGS_SIZE" rather than "ARG_SIZE", because it's the size of
all the arguments passed in registers rather than a single argument.  (Is there
a better term for this?  In Windows' x64 ABI, it's referred to as "shadow space"
here: http://en.wikipedia.org/wiki/X86_calling_conventions.)

[petarj, 2013/03/07 17:33:12]

Done.
There is no common name everybody uses for it.
I used "stack frame header" line for some other projects like v8.
GCC calls it "args_size".

 # define NACL_STACK_GETS_ARG        (0)
 # define NACL_STACK_PAD_BELOW_ALIGN (0)
 # define NACL_STACK_RED_ZONE        (0)