From a6a1052096c72660a24fead2e1e7d580ea4f8bc2 Mon Sep 17 00:00:00 2001
From: Michael Brown <mcb30@etherboot.org>
Date: Sun, 29 Jul 2007 00:17:25 +0100
Subject: [PATCH] Applied a modified version of holger's regparm patches.

---
 src/arch/i386/Config                   | 12 ++++++++++++
 src/arch/i386/core/relocate.c          |  2 +-
 src/arch/i386/interface/pcbios/int13.c |  2 +-
 src/arch/i386/interface/pxe/pxe_call.c |  4 ++--
 src/core/main.c                        |  2 +-
 src/include/compiler.h                 |  3 +++
 6 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/src/arch/i386/Config b/src/arch/i386/Config
index 87791321..16de411b 100644
--- a/src/arch/i386/Config
+++ b/src/arch/i386/Config
@@ -130,6 +130,18 @@ endif
 # this is almost always a win. the kernel uses it, too.
 CFLAGS+= -mpreferred-stack-boundary=2
 
+# use regparm for all functions - C functions called from assembly (or
+# vice versa) need __cdecl now
+CFLAGS+= -mregparm=3
+
+# use -mrtd (same __cdecl requirements as above)
+CFLAGS+= -mrtd
+
+# this is the logical complement to -mregparm=3. 
+# it doesn't currently buy us anything, but if anything ever tries
+# to return small structures, let's be prepared
+CFLAGS+= -freg-struct-return
+
 LDFLAGS+=	-N --no-check-sections
 
 ifeq "$(shell uname -s)" "FreeBSD"
diff --git a/src/arch/i386/core/relocate.c b/src/arch/i386/core/relocate.c
index d3b42d0d..39d00b09 100644
--- a/src/arch/i386/core/relocate.c
+++ b/src/arch/i386/core/relocate.c
@@ -39,7 +39,7 @@ extern char _end[];
  * address space, and returns the physical address of the new location
  * to the prefix in %edi.
  */
-void relocate ( struct i386_all_regs *ix86 ) {
+__cdecl void relocate ( struct i386_all_regs *ix86 ) {
 	struct memory_map memmap;
 	unsigned long start, end, size, padded_size;
 	unsigned long new_start, new_end;
diff --git a/src/arch/i386/interface/pcbios/int13.c b/src/arch/i386/interface/pcbios/int13.c
index f7cb6795..53817c7a 100644
--- a/src/arch/i386/interface/pcbios/int13.c
+++ b/src/arch/i386/interface/pcbios/int13.c
@@ -321,7 +321,7 @@ static int int13_get_extended_parameters ( struct int13_drive *drive,
  * INT 13 handler
  *
  */
-static void int13 ( struct i386_all_regs *ix86 ) {
+static __cdecl void int13 ( struct i386_all_regs *ix86 ) {
 	int command = ix86->regs.ah;
 	unsigned int bios_drive = ix86->regs.dl;
 	unsigned int original_bios_drive = bios_drive;
diff --git a/src/arch/i386/interface/pxe/pxe_call.c b/src/arch/i386/interface/pxe/pxe_call.c
index 834ca738..1c1b5066 100644
--- a/src/arch/i386/interface/pxe/pxe_call.c
+++ b/src/arch/i386/interface/pxe/pxe_call.c
@@ -112,7 +112,7 @@ static PXENV_EXIT_t pxenv_unknown ( struct s_PXENV_UNKNOWN *pxenv_unknown ) {
  * @v es:di		Address of PXE parameter block
  * @ret ax		PXE exit code
  */
-void pxe_api_call ( struct i386_all_regs *ix86 ) {
+__cdecl void pxe_api_call ( struct i386_all_regs *ix86 ) {
 	int opcode = ix86->regs.bx;
 	userptr_t parameters = real_to_user ( ix86->segs.es, ix86->regs.di );
 	size_t param_len;
@@ -304,7 +304,7 @@ void pxe_api_call ( struct i386_all_regs *ix86 ) {
  * @v es:di		Address of PXE parameter block
  * @ret ax		PXE exit code
  */
-void pxe_loader_call ( struct i386_all_regs *ix86 ) {
+__cdecl void pxe_loader_call ( struct i386_all_regs *ix86 ) {
 	userptr_t uparams = real_to_user ( ix86->segs.es, ix86->regs.di );
 	struct s_UNDI_LOADER params;
 	PXENV_EXIT_t ret;
diff --git a/src/core/main.c b/src/core/main.c
index 09dccc76..88fbb579 100644
--- a/src/core/main.c
+++ b/src/core/main.c
@@ -24,7 +24,7 @@ Literature dealing with the network protocols:
  *
  * @ret rc		Return status code
  */
-int main ( void ) {
+__cdecl int main ( void ) {
 
 	initialise();
 	startup();
diff --git a/src/include/compiler.h b/src/include/compiler.h
index 376936d0..b130f28f 100644
--- a/src/include/compiler.h
+++ b/src/include/compiler.h
@@ -276,6 +276,9 @@ extern void dbg_hex_dump_da ( unsigned long dispaddr,
 /** Declare a variable or data structure as unused. */
 #define __unused __attribute__ (( unused ))
 
+/** Apply standard C calling conventions */
+#define __cdecl __attribute__ (( cdecl , regparm(0) ))
+
 /**
  * Declare a function as used.
  *