From: H.J. Lu <hjl.tools@gmail.com>
Date: Tue, 11 Jan 2022 16:09:58 +0000 (-0800)
Subject: x86-64: Hide internal assembly functions
X-Git-Tag: v1.5.2^2~5^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F2993%2Fhead;p=thirdparty%2Fzstd.git

x86-64: Hide internal assembly functions

Hide x86-64 internal assembly functions. Before

$ nm -D lib/libzstd.so.1 | grep usingDTable_internal_bmi2_asm_loop
00000000000c23c0 T _HUF_decompress4X1_usingDTable_internal_bmi2_asm_loop
00000000000c23c0 T HUF_decompress4X1_usingDTable_internal_bmi2_asm_loop
00000000000c283d T _HUF_decompress4X2_usingDTable_internal_bmi2_asm_loop
00000000000c283d T HUF_decompress4X2_usingDTable_internal_bmi2_asm_loop
$

After

$ nm -D lib/libzstd.so.1 | grep usingDTable_internal_bmi2_asm_loop
$

This fixes issue #2990.
---

diff --git a/lib/common/portability_macros.h b/lib/common/portability_macros.h
index 627ef9eed..2143817f5 100644
--- a/lib/common/portability_macros.h
+++ b/lib/common/portability_macros.h
@@ -65,6 +65,12 @@
 # endif
 #endif
 
+/* Mark the internal assembly functions as hidden  */
+#ifdef __ELF__
+# define ZSTD_HIDE_ASM_FUNCTION(func) .hidden func
+#else
+# define ZSTD_HIDE_ASM_FUNCTION(func)
+#endif
 
 /* Enable runtime BMI2 dispatch based on the CPU.
  * Enabled for clang & gcc >=4.8 on x86 when BMI2 isn't enabled by default.
diff --git a/lib/decompress/huf_decompress.c b/lib/decompress/huf_decompress.c
index fa61968ba..202718825 100644
--- a/lib/decompress/huf_decompress.c
+++ b/lib/decompress/huf_decompress.c
@@ -664,7 +664,7 @@ size_t HUF_decompress4X1_usingDTable_internal_default(void* dst, size_t dstSize,
 
 #if ZSTD_ENABLE_ASM_X86_64_BMI2
 
-HUF_ASM_DECL void HUF_decompress4X1_usingDTable_internal_bmi2_asm_loop(HUF_DecompressAsmArgs* args);
+HUF_ASM_DECL void HUF_decompress4X1_usingDTable_internal_bmi2_asm_loop(HUF_DecompressAsmArgs* args) ZSTDLIB_HIDDEN;
 
 static HUF_ASM_X86_64_BMI2_ATTRS
 size_t
@@ -1380,7 +1380,7 @@ size_t HUF_decompress4X2_usingDTable_internal_default(void* dst, size_t dstSize,
 
 #if ZSTD_ENABLE_ASM_X86_64_BMI2
 
-HUF_ASM_DECL void HUF_decompress4X2_usingDTable_internal_bmi2_asm_loop(HUF_DecompressAsmArgs* args);
+HUF_ASM_DECL void HUF_decompress4X2_usingDTable_internal_bmi2_asm_loop(HUF_DecompressAsmArgs* args) ZSTDLIB_HIDDEN;
 
 static HUF_ASM_X86_64_BMI2_ATTRS size_t
 HUF_decompress4X2_usingDTable_internal_bmi2_asm(
diff --git a/lib/decompress/huf_decompress_amd64.S b/lib/decompress/huf_decompress_amd64.S
index 01bb6d767..49589cb61 100644
--- a/lib/decompress/huf_decompress_amd64.S
+++ b/lib/decompress/huf_decompress_amd64.S
@@ -30,6 +30,10 @@
  * TODO: Support Windows calling convention.
  */
 
+ZSTD_HIDE_ASM_FUNCTION(HUF_decompress4X1_usingDTable_internal_bmi2_asm_loop)
+ZSTD_HIDE_ASM_FUNCTION(HUF_decompress4X2_usingDTable_internal_bmi2_asm_loop)
+ZSTD_HIDE_ASM_FUNCTION(_HUF_decompress4X2_usingDTable_internal_bmi2_asm_loop)
+ZSTD_HIDE_ASM_FUNCTION(_HUF_decompress4X1_usingDTable_internal_bmi2_asm_loop)
 .global HUF_decompress4X1_usingDTable_internal_bmi2_asm_loop
 .global HUF_decompress4X2_usingDTable_internal_bmi2_asm_loop
 .global _HUF_decompress4X1_usingDTable_internal_bmi2_asm_loop