minipal: deduplicate inline header helpers

Keep small platform helpers inline for callers while providing one external fallback definition.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: mdh1418

src/native/minipal/CMakeLists.txt

@@ -9,6 +9,7 @@ set(SOURCES
     getexepath.c
     memorybarrierprocesswide.c
     mutex.c
+    ospagesize.c
     guid.c
     random.c
     debugger.c
@@ -20,19 +21,10 @@ set(SOURCES
     log.c
 )
 
-# ospagesize is provided inline in the header on Windows and WASM; the .c file
-# only contains the POSIX implementation. Including it on those platforms would
-# produce a redefinition error (mono builds for wasi/browser set HOST_WASM but
-# not CLR_CMAKE_TARGET_ARCH_WASM, so check both). In cross-component builds
-# (e.g. host=x64, target=wasm) the code runs on the host, so we still need the
-# POSIX implementation; only skip when the HOST is actually wasm.
-if(NOT WIN32 AND NOT HOST_WASM AND NOT (CLR_CMAKE_TARGET_ARCH_WASM AND NOT CLR_CROSS_COMPONENTS_BUILD))
-    list(APPEND SOURCES ospagesize.c)
-endif()
-
 if(CLR_CMAKE_HOST_UNIX)
     list(APPEND SOURCES
         cpucount.c
+        cpuid.c
         thread.c
     )
 endif()

src/native/minipal/cpuid.c

@@ -0,0 +1,18 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+#include "cpuid.h"
+
+#if defined(HOST_X86) || defined(HOST_AMD64)
+#if defined(HOST_UNIX)
+
+#if !__has_builtin(__cpuid)
+extern void __cpuid(int cpuInfo[4], int function_id);
+#endif
+
+#if !__has_builtin(__cpuidex)
+extern void __cpuidex(int cpuInfo[4], int function_id, int subFunction_id);
+#endif
+
+#endif // HOST_UNIX
+#endif // defined(HOST_X86) || defined(HOST_AMD64)

src/native/minipal/cpuid.h

@@ -16,13 +16,19 @@
 
 #include <minipal/utils.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 // MSVC directly defines intrinsics for __cpuid and __cpuidex matching the below signatures
 // We define matching signatures for use on Unix platforms.
 //
 // IMPORTANT: Unlike MSVC, Unix does not explicitly zero ECX for __cpuid
 
 #if !__has_builtin(__cpuid)
-static void __cpuid(int cpuInfo[4], int function_id)
+inline void __cpuid(int cpuInfo[4], int function_id) __asm("minipal_cpuid");
+
+inline void __cpuid(int cpuInfo[4], int function_id)
 {
     // Based on the Clang implementation provided in cpuid.h:
     // https://github.com/llvm/llvm-project/blob/main/clang/lib/Headers/cpuid.h
@@ -37,7 +43,9 @@ void __cpuid(int cpuInfo[4], int function_id);
 #endif
 
 #if !__has_builtin(__cpuidex)
-static void __cpuidex(int cpuInfo[4], int function_id, int subFunction_id)
+inline void __cpuidex(int cpuInfo[4], int function_id, int subFunction_id) __asm("minipal_cpuidex");
+
+inline void __cpuidex(int cpuInfo[4], int function_id, int subFunction_id)
 {
     // Based on the Clang implementation provided in cpuid.h:
     // https://github.com/llvm/llvm-project/blob/main/clang/lib/Headers/cpuid.h
@@ -51,6 +59,10 @@ static void __cpuidex(int cpuInfo[4], int function_id, int subFunction_id)
 void __cpuidex(int cpuInfo[4], int function_id, int subFunction_id);
 #endif
 
+#ifdef __cplusplus
+}
+#endif // extern "C"
+
 #endif // HOST_UNIX
 #endif // defined(HOST_X86) || defined(HOST_AMD64)
 

src/native/minipal/ospagesize.c

@@ -1,15 +1,17 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
-// POSIX implementation of minipal_getpagesize. On WASM and Windows the page size
-// is a compile-time constant and minipal_getpagesize is defined inline in the
-// header; this file is excluded from the build on those platforms by
-// src/native/minipal/CMakeLists.txt to avoid an empty translation unit.
+#include "ospagesize.h"
+
+#if defined(HOST_WASM) || defined(HOST_WINDOWS)
+
+extern uint32_t minipal_getpagesize(void);
+
+#else
 
 #include <unistd.h>
 #include <stdlib.h>
 #include <stdatomic.h>
-#include "ospagesize.h"
 
 uint32_t minipal_getpagesize(void)
 {
@@ -38,3 +40,5 @@ uint32_t minipal_getpagesize(void)
     }
     return page_size;
 }
+
+#endif // HOST_WASM || HOST_WINDOWS

src/native/minipal/ospagesize.h

@@ -19,15 +19,15 @@ extern "C" {
 // On other platforms the value is queried from the OS once and cached; the
 // definition lives in ospagesize.c so there is exactly one cache per process.
 #if defined(HOST_WASM)
-static inline uint32_t minipal_getpagesize(void)
+inline uint32_t minipal_getpagesize(void)
 {
     // WASM has no hardware pages; getpagesize() returns the 64KB memory.grow granularity,
     // which is too coarse for GC alignment and thresholds. Reduce the OS page size used
     // by the runtime on WASM to 16KB.
     return 16 * 1024;
 }
 #elif defined(HOST_WINDOWS)
-static inline uint32_t minipal_getpagesize(void)
+inline uint32_t minipal_getpagesize(void)
 {
     // The page size on Windows is 4KB and is not going to change.
     return 4 * 1024;