Alexandre Oliva writes:

This patch adds code to uClibc to support a new ABI designed for the
FR-V architecture, that enables text segments of executables and
shared libraries to be shared by multiple processes on an OS such as
uClinux, that can run on FR-V processors without an MMU.

Patches for binutils and GCC have just been posted in the
corresponding mailing lists.  The binutils patch was approved,
but there's one additional patch pending review, that I posted
this week.  An updated GCC patch will be posted to
gcc-patches@gcc.gnu.org as soon as I complete testing (I used a
known-good compiler to test the uClibc patch below).

Since the existing dynamic loader code didn't support independent
relocation of segments, it required changes that were somewhat
extensive.  I've added a number of new machine-specific macros to try
to keep the platform and ABI-specific details outside the generic
code.  I hope this is not a problem.

1 files changed, 95 insertions, 0 deletions

diff --git a/libc/sysdeps/linux/frv/setjmp.S b/libc/sysdeps/linux/frv/setjmp.S
new file mode 100644
index 000000000..455e61178
--- /dev/null
+++ b/libc/sysdeps/linux/frv/setjmp.S
@@ -0,0 +1,95 @@
+#include <features.h>
+#define _SETJMP_H
+#define _ASM
+#include <bits/setjmp.h>
+
+	.text
+
+/* This just does a tail-call to `__sigsetjmp (ARG, 0)'.
+   We cannot do it in C because it must be a tail-call, so frame-unwinding
+   in setjmp doesn't clobber the state restored by longjmp.  */
+
+	.global _setjmp
+	.type	_setjmp,@function
+_setjmp:
+	setlos	#0, gr9
+	bra	.Lsigsetjmp_intern
+	.size	_setjmp,.-_setjmp
+	
+/* This just does a tail-call to `__sigsetjmp (ARG, 1)'.
+   We cannot do it in C because it must be a tail-call, so frame-unwinding
+   in setjmp doesn't clobber the state restored by longjmp.  */
+
+	.align 4
+	.type	setjmp,@function
+	.globl	setjmp
+setjmp:	
+	setlos	#1, gr9
+	bra	.Lsigsetjmp_intern
+	.size	setjmp,.-setjmp
+	
+# setjmp/longjmp for Frv.  The jmpbuf looks like this:
+#	
+# Register	jmpbuf offset
+# R16-R31	0x0-0x03c
+# R48-R63	0x40-0x7c
+# FR16-FR31     0x80-0xbc
+# FR48-FR63     0xc0-0xfc
+# LR            0x100
+# SP            0x104
+# FP            0x108
+
+	.global	__sigsetjmp
+	.type	__sigsetjmp,@function
+__sigsetjmp:
+.Lsigsetjmp_intern:
+	stdi	gr16, @(gr8,0)
+	stdi	gr18, @(gr8,8)
+	stdi 	gr20, @(gr8,16)
+	stdi	gr22, @(gr8,24)
+	stdi	gr24, @(gr8,32)
+	stdi	gr26, @(gr8,40)
+	stdi	gr28, @(gr8,48)
+	stdi	gr30, @(gr8,56)
+#if __FRV_GPR__ != 32
+	stdi	gr48, @(gr8,64)
+	stdi	gr50, @(gr8,72)
+	stdi	gr52, @(gr8,80)
+	stdi	gr54, @(gr8,88)
+	stdi	gr56, @(gr8,96)
+	stdi	gr58, @(gr8,104)
+	stdi	gr60, @(gr8,112)
+	stdi	gr62, @(gr8,120)
+#endif
+
+#if __FRV_FPR__ != 0
+	stdfi	fr16, @(gr8,128)
+	stdfi	fr18, @(gr8,136)
+	stdfi 	fr20, @(gr8,144)
+	stdfi	fr22, @(gr8,152)
+	stdfi	fr24, @(gr8,160)
+	stdfi	fr26, @(gr8,168)
+	stdfi	fr28, @(gr8,176)
+	stdfi	fr30, @(gr8,184)
+#if __FRV_FPR__ != 32
+	stdfi	fr48, @(gr8,192)
+	stdfi	fr50, @(gr8,200)
+	stdfi	fr52, @(gr8,208)
+	stdfi	fr54, @(gr8,216)
+	stdfi	fr56, @(gr8,224)
+	stdfi	fr58, @(gr8,232)
+	stdfi	fr60, @(gr8,240)
+	stdfi	fr62, @(gr8,248)
+#endif
+#endif
+
+        movsg	lr, gr4
+	sti     gr4, @(gr8,256)
+	sti     sp, @(gr8,260)
+	sti     fp, @(gr8,264)
+	
+	sethi.p	#gotofffuncdeschi(__sigjmp_save), gr4
+	setlo	#gotofffuncdesclo(__sigjmp_save), gr4
+	ldd	@(gr15, gr4), gr14
+	jmpl	@(gr14, gr0)
+	.size	__sigsetjmp,.-__sigsetjmp