From b481c11e5a7eb409c76f56873d6378e7ff1e3e05 Mon Sep 17 00:00:00 2001
From: Anthony Green <green@moxielogic.com>
Date: Fri, 20 Dec 2019 09:00:26 -0500
Subject: [PATCH] Optimize setjmp/longjmp for moxie.

We don't need to save/restore every register -- just those
we don't expect to be trashed by function calls.
---
 newlib/libc/include/machine/setjmp.h |   2 +-
 newlib/libc/machine/moxie/setjmp.S   | 124 ++++++++-------------------
 2 files changed, 39 insertions(+), 87 deletions(-)

diff --git a/newlib/libc/include/machine/setjmp.h b/newlib/libc/include/machine/setjmp.h
index 78a81b5d9..55152b0d7 100644
--- a/newlib/libc/include/machine/setjmp.h
+++ b/newlib/libc/include/machine/setjmp.h
@@ -238,7 +238,7 @@ _BEGIN_STD_C
 #endif
 
 #ifdef __moxie__
-#define _JBLEN 19
+#define _JBLEN 10
 #endif
 
 #ifdef __CRX__
diff --git a/newlib/libc/machine/moxie/setjmp.S b/newlib/libc/machine/moxie/setjmp.S
index ed261d54d..014368d64 100644
--- a/newlib/libc/machine/moxie/setjmp.S
+++ b/newlib/libc/machine/moxie/setjmp.S
@@ -14,53 +14,34 @@
 # setjmp/longjmp for moxie.  The jmpbuf looks like this:
 #
 # Register        jmpbuf offset
-#   $r0             0x00
-#   $r1             0x04
-#   $r2             0x08
-#   $r3             0x0c
-#   $r4             0x10
-#   $r5             0x14
-#   $r6             0x18
-#   $r7             0x1c
-#   $r8             0x20
-#   $r9             0x24
-#   $r10            0x28
-#   $r11            0x2c
-#   $r12            0x30
-#   $r13            0x34
-#   $fp             0x38
-#   $sp             0x3c
-#   stack frame fp  0x40
-#   stack frame ra  0x44
-#   stack frame sc  0x48
+#   $r6             0x00
+#   $r7             0x04
+#   $r8             0x08
+#   $r9             0x0c
+#   $r10            0x10
+#   $fp             0x14
+#   $sp             0x18
+#   stack frame fp  0x1c
+#   stack frame ra  0x20
+#   stack frame sc  0x25
        
         .text
         .global setjmp
         .type   setjmp,@function
 setjmp:
-	st.l	($r0),     $r0
-	sto.l	0x04($r0), $r1
-	sto.l	0x08($r0), $r2
-	sto.l	0x0c($r0), $r3
-	sto.l	0x10($r0), $r4
-	sto.l	0x14($r0), $r5
-	sto.l	0x18($r0), $r6
-	sto.l	0x1c($r0), $r7
-	sto.l	0x20($r0), $r8
-	sto.l	0x24($r0), $r9
-	sto.l	0x28($r0), $r10
-	sto.l	0x2c($r0), $r11
-	sto.l	0x30($r0), $r12
-	sto.l	0x34($r0), $r13
-	sto.l	0x38($r0), $sp
-	sto.l	0x3c($r0), $fp
-	ldo.l   $r1,       0x0($fp)
-	sto.l   0x40($r0), $r1
+	st.l	($r0),     $r6
+	sto.l	0x04($r0), $r7
+	sto.l	0x08($r0), $r8
+	sto.l	0x0c($r0), $r9
+	sto.l	0x10($r0), $r10
+	sto.l	0x14($r0), $sp
+	sto.l	0x18($r0), $fp
+	ldo.l   $r1,       0x00($fp)
+	sto.l   0x1c($r0), $r1
 	ldo.l   $r1,       0x04($fp)
-	sto.l   0x44($r0), $r1
+	sto.l   0x20($r0), $r1
 	ldo.l   $r1,       0x08($fp)
-	sto.l   0x48($r0), $r1
-	ldo.l	$r1,       0x04($r0)
+	sto.l   0x24($r0), $r1
 	xor	$r0, $r0
 	ret
 .Lend1:
@@ -69,56 +50,27 @@ setjmp:
 	.global	longjmp
 	.type	longjmp,@function
 longjmp:
-	ldi.l	$r2, 0x00
-	cmp	$r1, $r2
-	beq	.Lreturn1
+	ldo.l	$r6, 0x00($r0)
+	ldo.l	$r7, 0x04($r0)
+	ldo.l	$r8, 0x08($r0)
+	ldo.l	$r9, 0x0c($r0)
+	ldo.l	$r10, 0x10($r0)
+	ldo.l	$sp, 0x14($r0)
+	ldo.l	$fp, 0x18($r0)
+	ldo.l   $r2, 0x1c($r0)
+	sto.l   0x0($fp), $r2
+	ldo.l   $r2, 0x20($r0)
+	sto.l   0x4($fp), $r2
+	ldo.l   $r2, 0x24($r0)
+	sto.l   0x8($fp), $r2
 	ldo.l	$r2, 0x08($r0)
-	ldo.l	$r3, 0x0c($r0)
-	ldo.l	$r4, 0x10($r0)
-	ldo.l	$r5, 0x14($r0)
-	ldo.l	$r6, 0x18($r0)
-	ldo.l	$r7, 0x1c($r0)
-	ldo.l	$r8, 0x20($r0)
-	ldo.l	$r9, 0x24($r0)
-	ldo.l	$r10, 0x28($r0)
-	ldo.l	$r11, 0x2c($r0)
-	ldo.l	$r12, 0x30($r0)
-	ldo.l	$r13, 0x34($r0)
-	ldo.l	$sp, 0x38($r0)
-	ldo.l	$fp, 0x3c($r0)
-	ldo.l   $r1, 0x40($r0)
-	sto.l   0x0($fp), $r1
-	ldo.l   $r1, 0x44($r0)
-	sto.l   0x4($fp), $r1
-	ldo.l   $r1, 0x48($r0)
-	sto.l   0x8($fp), $r1
-	ldo.l	$r1, 0x04($r0)
 	mov	$r0, $r1
+	xor	$r2, $r2
+	cmp	$r0, $r2
+	beq	.Lreturn1
 	ret
 .Lreturn1:
-	ldo.l	$r1, 0x04($r0)
-	ldo.l	$r2, 0x08($r0)
-	ldo.l	$r3, 0x0c($r0)
-	ldo.l	$r4, 0x10($r0)
-	ldo.l	$r5, 0x14($r0)
-	ldo.l	$r6, 0x18($r0)
-	ldo.l	$r7, 0x1c($r0)
-	ldo.l	$r8, 0x20($r0)
-	ldo.l	$r9, 0x24($r0)
-	ldo.l	$r10, 0x28($r0)
-	ldo.l	$r11, 0x2c($r0)
-	ldo.l	$r12, 0x30($r0)
-	ldo.l	$r13, 0x34($r0)
-	ldo.l	$sp, 0x38($r0)
-	ldo.l	$fp, 0x3c($r0)
-	ldo.l   $r1, 0x40($r0)
-	sto.l   0x0($fp), $r1
-	ldo.l   $r1, 0x44($r0)
-	sto.l   0x4($fp), $r1
-	ldo.l   $r1, 0x48($r0)
-	sto.l   0x8($fp), $r1
-	ldo.l	$r1, 0x04($r0)
-	ldi.l	$r0, 0x01
+	inc     $r0, 1
 	ret
 .Lend2:
 	.size	longjmp,.Lend2-longjmp