[newlib-cygwin] or1k: Avoid write outside setjmp buf & shrink buf

[newlib-cygwin] or1k: Avoid write outside setjmp buf & shrink buf

[Corinna Vinschen]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=739e89cbe6d0f416d9799e1c296d2d15d7fac4e5

commit 739e89cbe6d0f416d9799e1c296d2d15d7fac4e5
Author: Martin Erik Werner <martinerikwerner.aac@gmail.com>
Date:   Thu Jun 27 10:03:48 2019 +0200

    or1k: Avoid write outside setjmp buf & shrink buf
    
    Update the offsets used to save registers into the stejmp jmp_buf
    structure in order to:
    
    * Avoid writing the supervision register outside the buffer and thus
      clobbering something on the stack. Previously the supervision register
      was written at offset 124 while the buffer was of length 124.
    
    * Shrink the jmp_buf down to the size actually needed, by avoiding holes
      at the locations of omitted registers.

Diff:
---
 newlib/libc/include/machine/setjmp.h |  5 +++-
 newlib/libc/machine/or1k/setjmp.S    | 56 ++++++++++++++++++------------------
 2 files changed, 32 insertions(+), 29 deletions(-)

diff --git a/newlib/libc/include/machine/setjmp.h b/newlib/libc/include/machine/setjmp.h
index 9212f84..6b37bcc 100644
--- a/newlib/libc/include/machine/setjmp.h
+++ b/newlib/libc/include/machine/setjmp.h
@@ -2,7 +2,10 @@
 _BEGIN_STD_C
 
 #if defined(__or1k__) || defined(__or1knd__)
-#define _JBLEN 31 /* 32 GPRs - r0 */
+/*
+ * r1, r2, r9, r14, r16 .. r30, SR.
+ */
+#define _JBLEN 13
 #define _JBTYPE unsigned long
 #endif
 
diff --git a/newlib/libc/machine/or1k/setjmp.S b/newlib/libc/machine/or1k/setjmp.S
index 0b93a03..f0663f3 100644
--- a/newlib/libc/machine/or1k/setjmp.S
+++ b/newlib/libc/machine/or1k/setjmp.S
@@ -29,25 +29,25 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 .type   setjmp,@function
 setjmp:
 
-	l.sw	4(r3), r1
-	l.sw	8(r3), r2
+	l.sw	0(r3), r1
+	l.sw	4(r3), r2
 	/* Skip r3-r8 as they are not preserved across function calls */
-	l.sw	36(r3), r9
+	l.sw	8(r3), r9
 	/* Skip r10 as it's preserved to be used by TLS */ 
 	/* Skip r11, setjmp always set it to 0 */
 	/* The following set if registers are preserved across function calls */
-	l.sw	52(r3), r14
-	l.sw	60(r3), r16
-	l.sw	68(r3), r18
-	l.sw	76(r3), r20
-	l.sw	84(r3), r22
-	l.sw	92(r3), r24
-	l.sw	100(r3), r26
-	l.sw	108(r3), r28
-	l.sw	116(r3), r30
+	l.sw	12(r3), r14
+	l.sw	16(r3), r16
+	l.sw	20(r3), r18
+	l.sw	24(r3), r20
+	l.sw	28(r3), r22
+	l.sw	32(r3), r24
+	l.sw	36(r3), r26
+	l.sw	40(r3), r28
+	l.sw	44(r3), r30
 	/* Save Status Register */
 	l.mfspr	r13, r0, 17
-	l.sw	124(r3), r13
+	l.sw	48(r3), r13
 /* Set result register to 0 and jump */
 // Different cases for optional delay slot
 #if defined(__OR1K_NODELAY__)
@@ -77,32 +77,32 @@ longjmp:
 
   /* Load status register */
 1: 
-	l.lwz	r15, 124(r3)
+	l.lwz	r15, 48(r3)
 	l.mtspr	r0, r15, 17
 
-	l.lwz	r1, 4(r3)
-	l.lwz	r2, 8(r3)
+	l.lwz	r1, 0(r3)
+	l.lwz	r2, 4(r3)
 	/* Skip r3-r8 as they are not preserved across function calls */
-	l.lwz	r9, 36(r3)
+	l.lwz	r9, 8(r3)
 	/* Skip r11 as it's always set by longjmp */
-	l.lwz	r14, 52(r3)
-	l.lwz	r16, 60(r3)
-	l.lwz	r18, 68(r3)
-	l.lwz	r20, 76(r3)
-	l.lwz	r22, 84(r3)
-	l.lwz	r24, 92(r3)
-	l.lwz	r26, 100(r3)
-	l.lwz	r28, 108(r3)
+	l.lwz	r14, 12(r3)
+	l.lwz	r16, 16(r3)
+	l.lwz	r18, 20(r3)
+	l.lwz	r20, 24(r3)
+	l.lwz	r22, 28(r3)
+	l.lwz	r24, 32(r3)
+	l.lwz	r26, 36(r3)
+	l.lwz	r28, 40(r3)
 
 // Different cases for optional delay slot
 #if defined(__OR1K_NODELAY__)
-	l.lwz	r30, 116(r3)
+	l.lwz	r30, 44(r3)
 	l.jr	r9
 #elif defined(__OR1K_DELAY__)
 	l.jr	r9
-	l.lwz	r30, 116(r3)
+	l.lwz	r30, 44(r3)
 #else
-	l.lwz	r30, 116(r3)
+	l.lwz	r30, 44(r3)
 	l.jr	r9
 	l.nop
 #endif