From 8d9f4e0d6e18cae5174bb26f16655a7eb50f4f01 Mon Sep 17 00:00:00 2001
From: mirabilos <tg@debian.org>
Date: Sun, 26 Dec 2021 23:17:05 +0000
Subject: [PATCH] {set,long}jmp [s390x]: save/restore the correct registers
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Forwarded: https://lists.zytor.com/archives/klibc/2021-May/004620.html

The s390x ABI actually has FPU registers f8‥f15, not f1/f3/f5/f7,
to be saved. (Closes: Debian #943425)

Gbp-Pq: Name 0041-klibc-set-long-jmp-s390x-save-restore-the-correct-re.patch
---
 usr/include/arch/s390/klibc/archsetjmp.h |  2 +-
 usr/klibc/arch/s390/setjmp.S             | 24 ++++++++++++++++--------
 2 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/usr/include/arch/s390/klibc/archsetjmp.h b/usr/include/arch/s390/klibc/archsetjmp.h
index 728780a..1167c8b 100644
--- a/usr/include/arch/s390/klibc/archsetjmp.h
+++ b/usr/include/arch/s390/klibc/archsetjmp.h
@@ -16,7 +16,7 @@ struct __jmp_buf {
 
 struct __jmp_buf {
 	uint64_t __gregs[10]; /* general registers r6-r15 */
-	uint64_t __fpregs[4]; /* fp registers f1, f3, f5, f7 */
+	uint64_t __fpregs[8]; /* fp registers f8-f15 */
 };
 
 #endif /* __s390x__ */
diff --git a/usr/klibc/arch/s390/setjmp.S b/usr/klibc/arch/s390/setjmp.S
index c36a051..1386419 100644
--- a/usr/klibc/arch/s390/setjmp.S
+++ b/usr/klibc/arch/s390/setjmp.S
@@ -38,10 +38,14 @@ longjmp:
 
 setjmp:
 	stmg	%r6,%r15,0(%r2)		# save all general registers
-	std	%f1,80(%r2)		# save fp registers f4 and f6
-	std	%f3,88(%r2)
-	std	%f5,96(%r2)
-	std	%f7,104(%r2)
+	std	%f8,80(%r2)		# save fp registers f8 to f15
+	std	%f9,88(%r2)
+	std	%f10,96(%r2)
+	std	%f11,104(%r2)
+	std	%f12,112(%r2)
+	std	%f13,120(%r2)
+	std	%f14,128(%r2)
+	std	%f15,136(%r2)
 	lghi	%r2,0			# return 0
 	br	%r14
 
@@ -54,10 +58,14 @@ setjmp:
 longjmp:
 	lgr	%r1,%r2			# jmp_buf
 	lgr	%r2,%r3			# return value
-	ld	%f7,104(%r1)		# restore all saved registers
-	ld	%f5,96(%r1)
-	ld	%f3,88(%r1)
-	ld	%f1,80(%r1)
+	ld	%f15,136(%r1)		# restore all saved registers
+	ld	%f14,128(%r1)
+	ld	%f13,120(%r1)
+	ld	%f12,112(%r1)
+	ld	%f11,104(%r1)
+	ld	%f10,96(%r1)
+	ld	%f9,88(%r1)
+	ld	%f8,80(%r1)
 	lmg	%r6,%r15,0(%r1)
 	br	%r14			# return to restored address
 
-- 
2.30.2