From mboxrd@z Thu Jan  1 00:00:00 1970
From: Graeme Russ <graeme.russ@gmail.com>
Date: Sun, 14 Nov 2010 16:48:17 +1100
Subject: [U-Boot] RFC: Aligning arch initialisation sequences
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On 14/11/10 16:10, Graeme Russ wrote:
> On 13/11/10 22:18, Graeme Russ wrote:
>> On 13/11/10 19:20, Albert ARIBAUD wrote:
>>> Le 13/11/2010 05:16, Graeme Russ a ?crit :
>>>

> static inline void *get_gd_ptr(void)
> {
> 	void *gd_ptr;
> 
> 	asm volatile("gs mov 0, %0\n" : "=r" (gd_ptr));
> 	return gd_ptr;
> }
> 

static inline gd_t *get_gd_ptr(void)
{
	gd_t *gd_ptr;

	asm volatile("fs mov 0, %0\n" : "=r" (gd_ptr));
	return gd_ptr;
}

works a treat :)

Is there any reason the other arches could not implement an inline function
as well? ARM for example:

-#define DECLARE_GLOBAL_DATA_PTR     register volatile gd_t *gd asm ("r8")

+static inline gd_t *gd(void)
+{
+	gd_t *gd_ptr;
+
+	asm volatile("mov r8, %0\n" : "=r" (gd_ptr));
+	return gd_ptr;
+}

Is the compiler smart enough to optimise out and not increase code size?

If so, all the arches can have identical implementations for using global data

Regards,

Graeme