From: H.J. Lu <hjl.tools@gmail.com>
Date: Fri, 22 Apr 2022 17:53:13 +0000 (-0700)
Subject: x86-64: Fix SSE2 memcmp and SSSE3 memmove for x32
X-Git-Tag: glibc-2.36~350
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=8ea20ee5f6145de4bff9481d3e09ac36ba9df8f3;p=thirdparty%2Fglibc.git

x86-64: Fix SSE2 memcmp and SSSE3 memmove for x32

Clear the upper 32 bits in RDX (memory size) for x32 to fix

FAIL: string/tst-size_t-memcmp
FAIL: string/tst-size_t-memcmp-2
FAIL: string/tst-size_t-memcpy
FAIL: wcsmbs/tst-size_t-wmemcmp

on x32 introduced by

8804157ad9 x86: Optimize memcmp SSE2 in memcmp.S
26b2478322 x86: Reduce code size of mem{move|pcpy|cpy}-ssse3

Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
---

diff --git a/sysdeps/x86_64/memcmp.S b/sysdeps/x86_64/memcmp.S
index b1536940482..5718a7da862 100644
--- a/sysdeps/x86_64/memcmp.S
+++ b/sysdeps/x86_64/memcmp.S
@@ -46,6 +46,10 @@
 
 	.text
 ENTRY(MEMCMP)
+# ifdef __ILP32__
+	/* Clear the upper 32 bits.  */
+	movl	%edx, %edx
+# endif
 #ifdef USE_AS_WMEMCMP
 	/* Use 0xffff to test for mismatches on pmovmskb bitmask. Store
 	   in ecx for code size. This is preferable to using `incw` as
diff --git a/sysdeps/x86_64/multiarch/memmove-ssse3.S b/sysdeps/x86_64/multiarch/memmove-ssse3.S
index 215583e7bdf..310ff62b86d 100644
--- a/sysdeps/x86_64/multiarch/memmove-ssse3.S
+++ b/sysdeps/x86_64/multiarch/memmove-ssse3.S
@@ -27,6 +27,10 @@ ENTRY(MEMMOVE_CHK)
 END(MEMMOVE_CHK)
 
 ENTRY_P2ALIGN(MEMMOVE, 6)
+# ifdef __ILP32__
+	/* Clear the upper 32 bits.  */
+	movl	%edx, %edx
+# endif
 	movq	%rdi, %rax
 L(start):
 	cmpq	$16, %rdx