Stop ARM setjmp/longjmp saving/restoring fpscr (bug 14908).

5 files changed, 18 insertions, 20 deletions

diff --git a/NEWS b/NEWS
index 027ceab..72c6a1c 100644
--- a/NEWS
+++ b/NEWS
@@ -11,13 +11,13 @@ Version 2.18
 
   2546, 2560, 5159, 6809, 10060, 10062, 10357, 11120, 11561, 12387, 12723,
   13550, 13889, 13951, 13988, 14142, 14176, 14200, 14280, 14293, 14317,
-  14327, 14478, 14496, 14582, 14686, 14812, 14888, 14920, 14952, 14964,
-  14981, 14982, 14985, 14994, 14996, 15003, 15006, 15007, 15020, 15023,
-  15036, 15054, 15055, 15062, 15078, 15084, 15085, 15086, 15160, 15214,
-  15221, 15232, 15234, 15283, 15285, 15287, 15304, 15305, 15307, 15309,
-  15327, 15330, 15335, 15336, 15337, 15342, 15346, 15359, 15361, 15366,
-  15380, 15394, 15395, 15405, 15406, 15409, 15416, 15418, 15419, 15423,
-  15426, 15429, 15448.
+  14327, 14478, 14496, 14582, 14686, 14812, 14888, 14908, 14920, 14952,
+  14964, 14981, 14982, 14985, 14994, 14996, 15003, 15006, 15007, 15020,
+  15023, 15036, 15054, 15055, 15062, 15078, 15084, 15085, 15086, 15160,
+  15214, 15221, 15232, 15234, 15283, 15285, 15287, 15304, 15305, 15307,
+  15309, 15327, 15330, 15335, 15336, 15337, 15342, 15346, 15359, 15361,
+  15366, 15380, 15394, 15395, 15405, 15406, 15409, 15416, 15418, 15419,
+  15423, 15426, 15429, 15448.
 
 * CVE-2013-0242 Buffer overrun in regexp matcher has been fixed (Bugzilla
   #15078).
diff --git a/ports/ChangeLog.arm b/ports/ChangeLog.arm
index 2565518..ce5fc36 100644
--- a/ports/ChangeLog.arm
+++ b/ports/ChangeLog.arm
@@ -1,3 +1,11 @@
+2013-05-14  Joseph Myers  <joseph@codesourcery.com>
+
+	[BZ #14908]
+	* sysdeps/arm/setjmp.S (__sigsetjmp): Don't save fpscr.
+	* sysdeps/arm/__longjmp.S (__longjmp): Don't restore fpscr.
+	* sysdeps/arm/bits/setjmp.h (__jmp_buf): Don't mention fpscr in
+	comment.
+
 2013-05-13  Roland McGrath  <roland@hack.frob.com>
 
 	* sysdeps/arm/armv7/multiarch/memcpy.S [__ARM_NEON__]: Don't define
diff --git a/ports/sysdeps/arm/__longjmp.S b/ports/sysdeps/arm/__longjmp.S
index 8de9fa1..a5edede 100644
--- a/ports/sysdeps/arm/__longjmp.S
+++ b/ports/sysdeps/arm/__longjmp.S
@@ -83,11 +83,6 @@ ENTRY (__longjmp)
 	/* Following instruction is vldmia ip!, {d8-d15}.  */
 	sfi_breg r12, \
 	ldc	p11, cr8, [\B], #64
-	/* Restore the floating-point status register.  */
-	sfi_breg ip, \
-	ldr     a3, [\B], #4
-	/* Following instruction is fmxr fpscr, a3.  */
-	mcr	p10, 7, a3, cr1, cr0, 0
 .Lno_vfp:
 
 #ifndef ARM_ASSUME_NO_IWMMXT
diff --git a/ports/sysdeps/arm/bits/setjmp.h b/ports/sysdeps/arm/bits/setjmp.h
index 21bbf7f..c8c3a9a 100644
--- a/ports/sysdeps/arm/bits/setjmp.h
+++ b/ports/sysdeps/arm/bits/setjmp.h
@@ -28,9 +28,9 @@
 /* The exact set of registers saved may depend on the particular core
    in use, as some coprocessor registers may need to be saved.  The C
    Library ABI requires that the buffer be 8-byte aligned, and
-   recommends that the buffer contain 64 words.  The first 28 words
-   are occupied by v1-v6, sl, fp, sp, pc, d8-d15, and fpscr.  (Note
-   that d8-15 require 17 words, due to the use of fstmx.)  */
+   recommends that the buffer contain 64 words.  The first 27 words
+   are occupied by v1-v6, sl, fp, sp, pc, and d8-d15.  (Note that
+   d8-15 require 17 words, due to the use of fstmx.)  */
 typedef int __jmp_buf[64] __attribute__((__aligned__ (8)));
 #endif
 
diff --git a/ports/sysdeps/arm/setjmp.S b/ports/sysdeps/arm/setjmp.S
index f750470..a6c161d 100644
--- a/ports/sysdeps/arm/setjmp.S
+++ b/ports/sysdeps/arm/setjmp.S
@@ -67,11 +67,6 @@ ENTRY (__sigsetjmp)
 	/* Following instruction is vstmia ip!, {d8-d15}.  */
 	sfi_breg ip, \
 	stc	p11, cr8, [\B], #64
-	/* Store the floating-point status register.  */
-	/* Following instruction is vmrs a4, fpscr.  */
-	mrc	p10, 7, a4, cr1, cr0, 0
-	sfi_breg ip, \
-	str	a4, [\B], #4
 .Lno_vfp:
 
 #ifndef ARM_ASSUME_NO_IWMMXT