整理初版

third_party/asmjit/core/environment.cpp

@@ -0,0 +1,46 @@
+// This file is part of AsmJit project <https://asmjit.com>
+//
+// See asmjit.h or LICENSE.md for license and copyright information
+// SPDX-License-Identifier: Zlib
+
+#include "../core/api-build_p.h"
+#include "../core/environment.h"
+
+ASMJIT_BEGIN_NAMESPACE
+
+// X86 Target
+// ----------
+//
+//   - 32-bit - Linux, OSX, BSD, and apparently also Haiku guarantee 16-byte
+//              stack alignment. Other operating systems are assumed to have
+//              4-byte alignment by default for safety reasons.
+//   - 64-bit - stack must be aligned to 16 bytes.
+//
+// ARM Target
+// ----------
+//
+//   - 32-bit - Stack must be aligned to 8 bytes.
+//   - 64-bit - Stack must be aligned to 16 bytes (hardware requirement).
+uint32_t Environment::stackAlignment() const noexcept {
+  if (is64Bit()) {
+    // Assume 16-byte alignment on any 64-bit target.
+    return 16;
+  }
+  else {
+    // The following platforms use 16-byte alignment in 32-bit mode.
+    if (isPlatformLinux() ||
+        isPlatformBSD() ||
+        isPlatformApple() ||
+        isPlatformHaiku()) {
+      return 16u;
+    }
+
+    if (isFamilyARM())
+      return 8;
+
+    // Bail to 4-byte alignment if we don't know.
+    return 4;
+  }
+}
+
+ASMJIT_END_NAMESPACE