From: Pavel P <pavlov.pavel@gmail.com>
Date: Sat, 18 Jan 2025 03:01:43 +0000 (+0200)
Subject: [asm] Enable x86_64 asm for windows builds
X-Git-Tag: v1.5.7^2~30^2~1
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=46e17b805b1bb2982583208da3b9184e377c2dd5;p=thirdparty%2Fzstd.git

[asm] Enable x86_64 asm for windows builds
---

diff --git a/lib/common/portability_macros.h b/lib/common/portability_macros.h
index b1d9765fb..1ca28af6a 100644
--- a/lib/common/portability_macros.h
+++ b/lib/common/portability_macros.h
@@ -93,7 +93,7 @@
  * Only enable assembly for GNU C compatible compilers,
  * because other platforms may not support GAS assembly syntax.
  *
- * Only enable assembly for Linux / MacOS, other platforms may
+ * Only enable assembly for Linux / MacOS / Win32, other platforms may
  * work, but they haven't been tested. This could likely be
  * extended to BSD systems.
  *
@@ -101,10 +101,8 @@
  * 100% of code to be instrumented to work.
  */
 #if defined(__GNUC__)
-#  if defined(__linux__) || defined(__linux) || defined(__APPLE__)
-#    if ZSTD_MEMORY_SANITIZER
-#      define ZSTD_ASM_SUPPORTED 0
-#    elif ZSTD_DATAFLOW_SANITIZER
+#  if defined(__linux__) || defined(__linux) || defined(__APPLE__) || defined(_WIN32)
+#    if ZSTD_MEMORY_SANITIZER || ZSTD_DATAFLOW_SANITIZER
 #      define ZSTD_ASM_SUPPORTED 0
 #    else
 #      define ZSTD_ASM_SUPPORTED 1
diff --git a/lib/decompress/huf_decompress_amd64.S b/lib/decompress/huf_decompress_amd64.S
index 78da291ee..656aada95 100644
--- a/lib/decompress/huf_decompress_amd64.S
+++ b/lib/decompress/huf_decompress_amd64.S
@@ -42,13 +42,11 @@
 
 /* Calling convention:
  *
- * %rdi contains the first argument: HUF_DecompressAsmArgs*.
+ * %rdi (or %rcx on Windows) contains the first argument: HUF_DecompressAsmArgs*.
  * %rbp isn't maintained (no frame pointer).
  * %rsp contains the stack pointer that grows down.
  *      No red-zone is assumed, only addresses >= %rsp are used.
  * All register contents are preserved.
- *
- * TODO: Support Windows calling convention.
  */
 
 ZSTD_HIDE_ASM_FUNCTION(HUF_decompress4X1_usingDTable_internal_fast_asm_loop)
@@ -137,7 +135,11 @@ HUF_decompress4X1_usingDTable_internal_fast_asm_loop:
     push %r15
 
     /* Read HUF_DecompressAsmArgs* args from %rax */
+#if defined(_WIN32)
+    movq %rcx, %rax
+#else
     movq %rdi, %rax
+#endif
     movq  0(%rax), %ip0
     movq  8(%rax), %ip1
     movq 16(%rax), %ip2
@@ -391,7 +393,12 @@ HUF_decompress4X2_usingDTable_internal_fast_asm_loop:
     push %r14
     push %r15
 
+    /* Read HUF_DecompressAsmArgs* args from %rax */
+#if defined(_WIN32)
+    movq %rcx, %rax
+#else
     movq %rdi, %rax
+#endif
     movq  0(%rax), %ip0
     movq  8(%rax), %ip1
     movq 16(%rax), %ip2