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ARM EABI setjmp/longjmp fixes


I've applied this patch to fix two problems with ARM EABI
setjmp/longjmp:

* setjmp and longjmp were using the obsolete fstmiax and fldmiax
  instructions.

* Because of a confusion with two different sets of names for the same
  registers (r0...r3 and a1...a4), if VFP was present then the
  subsequent check for iWMMXt support would use a register that had
  been clobbered by saving/restoring the VFP registers.  (The bit
  being checked was clobbered by a reserved bit of FPSCR that it
  always 0 on present hardware, and no present hardware has both VFP
  and iWMMXt, so this did not cause visible problems.)

diff --git a/ChangeLog.arm b/ChangeLog.arm
index 643a071..f098f3c 100644
--- a/ChangeLog.arm
+++ b/ChangeLog.arm
@@ -1,3 +1,12 @@
+2009-10-22  Andrew Stubbs  <ams@codesourcery.com>
+            Julian Brown  <julian@codesourcery.com>
+
+	* sysdeps/arm/eabi/setjmp.S (__sigsetjmp): Replace deprecated
+	instruction fstmiax with vstmia.
+	Correct register conflict and comment.
+	* sysdeps/arm/eabi/__longjmp.S (__longjmp): Use vldmia not fldmiax.
+	Don't clobber r1/a2 register before testing IWMMXT hwcap.
+
 2009-10-22  Julian Brown  <julian@codesourcery.com>
 
 	* sysdeps/arm/elf/start.S (_start): Avoid dependency on PC pipeline
diff --git a/sysdeps/arm/eabi/__longjmp.S b/sysdeps/arm/eabi/__longjmp.S
index f283297..3059193 100644
--- a/sysdeps/arm/eabi/__longjmp.S
+++ b/sysdeps/arm/eabi/__longjmp.S
@@ -59,12 +59,12 @@ ENTRY (__longjmp)
 	beq	Lno_vfp
 
 	/* Restore the VFP registers.  */
-	/* Following instruction is fldmiax ip!, {d8-d15}.  */
-	ldc	p11, cr8, [r12], #68
+	/* Following instruction is vldmia ip!, {d8-d15}.  */
+	ldc	p11, cr8, [r12], #64
 	/* Restore the floating-point status register.  */
-	ldr     r1, [ip], #4
-	/* Following instruction is fmxr fpscr, r1.  */
-	mcr	p10, 7, r1, cr1, cr0, 0
+	ldr     a3, [ip], #4
+	/* Following instruction is fmxr fpscr, a3.  */
+	mcr	p10, 7, a3, cr1, cr0, 0
 Lno_vfp:
 
 	tst	a2, #HWCAP_ARM_IWMMXT
diff --git a/sysdeps/arm/eabi/setjmp.S b/sysdeps/arm/eabi/setjmp.S
index 835db71..92f83af 100644
--- a/sysdeps/arm/eabi/setjmp.S
+++ b/sysdeps/arm/eabi/setjmp.S
@@ -52,13 +52,15 @@ ENTRY (__sigsetjmp)
 	tst	a3, #HWCAP_ARM_VFP
 	beq	Lno_vfp
 
-	/* Store the VFP registers.  */
-	/* Following instruction is fstmiax ip!, {d8-d15}.  */
-	stc	p11, cr8, [r12], #68
+	/* Store the VFP registers.
+	   Don't use VFP instructions directly because this code
+	   is used in non-VFP multilibs.  */
+	/* Following instruction is vstmia ip!, {d8-d15}.  */
+	stc	p11, cr8, [ip], #64
 	/* Store the floating-point status register.  */
-	/* Following instruction is fmrx r2, fpscr.  */
-	mrc	p10, 7, r2, cr1, cr0, 0
-	str	r2, [ip], #4
+	/* Following instruction is vmrs a4, fpscr.  */
+	mrc	p10, 7, a4, cr1, cr0, 0
+	str	a4, [ip], #4
 Lno_vfp:
 
 	tst	a3, #HWCAP_ARM_IWMMXT

-- 
Joseph S. Myers
joseph@codesourcery.com


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