From: Stefan Liebler <stli@linux.vnet.ibm.com>
Date: Tue, 24 May 2016 08:39:13 +0000 (+0200)
Subject: S390: Use 64bit instruction to check for copies of > 1MB with mvcle.
X-Git-Tag: glibc-2.24~222
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=074b0f27d9b9cdfb58c5c7e7f4129546084582b2;p=thirdparty%2Fglibc.git

S390: Use 64bit instruction to check for copies of > 1MB with mvcle.

The __memcpy_default variant on s390 64bit calculates the number of
256byte blocks in a 64bit register and checks, if they exceed 1MB
to jump to mvcle. Otherwise a mvc-loop is used. The compare-instruction
only checks a 32bit value.
This patch uses a 64bit compare.

ChangeLog:

	* sysdeps/s390/s390-64/memcpy.S (memcpy):
	Use cghi instead of chi to compare 64bit value.
---

diff --git a/ChangeLog b/ChangeLog
index d2b34a84786..1bacd7172e9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2016-05-24  Stefan Liebler  <stli@linux.vnet.ibm.com>
+
+	* sysdeps/s390/s390-64/memcpy.S (memcpy):
+	Use cghi instead of chi to compare 64bit value.
+
 2016-05-24  Stefan Liebler  <stli@linux.vnet.ibm.com>
 
 	* sysdeps/s390/s390-32/memcpy.S (memcpy):
diff --git a/sysdeps/s390/s390-64/memcpy.S b/sysdeps/s390/s390-64/memcpy.S
index e84a3572cbd..9d60a14cccd 100644
--- a/sysdeps/s390/s390-64/memcpy.S
+++ b/sysdeps/s390/s390-64/memcpy.S
@@ -47,7 +47,7 @@ ENTRY(memcpy)
 .L_Z900_4:
 	br      %r14
 .L_Z900_13:
-	chi	%r5,4096             # Switch to mvcle for copies >1MB
+	cghi	%r5,4096            # Switch to mvcle for copies >1MB
 	jh      __memcpy_mvcle
 .L_Z900_12:
 	mvc     0(256,%r1),0(%r3)