macOS (Apple Silicon) support: native build running under Rosetta 2 with MoltenVK (#102)

* macos: POSIX platform layer (host fault handler, virtual memory)

- hostException: Mach/POSIX signal-based host fault handler mirroring the
  Windows vectored handler (SIGSEGV/SIGBUS/SIGILL), behind
  '#elif defined(__APPLE__)'. Windows and Linux branches are untouched.
- sysLinuxVirtual: mach_vm_region-based is_mapped (no /proc/self/maps on
  macOS), PTHREAD_MUTEX_NORMAL, and a MAP_FIXED carve-in-place allocator that
  never leaves an unmapped hole for dyld/Rosetta/Metal to claim. All
  __APPLE__-guarded; the original Linux allocator path is preserved verbatim.
- sysLinuxDbg/sysLinuxFileIO: libgen.h for basename(), and a POSIX
  opendir/readdir implementation of SysFileGetDents (previously a stub).

* macos: guest kernel backing, threads, and POSIX libs

- memory/memoryAddressSpace: anonymous shm_open backing (macOS has no
  memfd_create) and re-reserve-on-unmap so a guest MAP_FIXED remap never
  destroys a host mapping (__APPLE__-guarded). Drops host <sys/mman.h> MAP_*
  macros so the guest's constexpr MAP_* constants compile (no-op on Windows).
- pthread: undef the host PTHREAD_STACK_MIN macro; on non-Windows, pin the
  stack-switch asm's guest rsp/rbp to callee-saved r14/r15 (the template
  clobbers r12/r13); __APPLE__ no-op for the absent pthread_condattr_setclock.
  The Windows stack-switch asm is byte-identical.
- network: define SOCKET/INVALID_SOCKET for the non-Windows paths (were
  undefined at 20+ use sites), and rename the non-Windows kernel_clock_*
  helpers to the CamelCase names the callers already use. Both repair the
  shared non-Windows build. Integer reinterpret_cast -> static_cast.

* loader: pin stack-switch asm operands to callee-saved registers

RunEntry switches to the guest stack with an asm template that clobbers
r12/r13 before consuming its inputs. With plain "r" constraints the compiler
may place func/guest_rsp/guest_rbp into r12/r13, so 'callq *func' jumps
through the saved host rsp -- a latent miscompile on every platform that any
unrelated codegen change can trigger. Pin the inputs to rbx/r14/r15, which the
template never touches and the SysV callee preserves.

General correctness fix (not macOS-specific); the same fix is applied to
pthread RunOnGuestStack.

* macos: Vulkan/MoltenVK graphics enablement

- pageManager: GPU write-tracking via Mach VM queries + mprotect (mprotect
  cannot report the previous protection, so the expected-old check is dropped),
  thread id via pthread_mach_thread_np, 4 KB page-size check -- __APPLE__-guarded.
- shaders/renderDraw/vulkanWindow: MoltenVK lacks VK_EXT_color_write_enable,
  VK_EXT_depth_clip_enable and depthBounds; fall back to static color-write
  masks and default depth clipping, request VK_KHR_portability_subset, and
  reuse the graphics queue for present when only one queue is exposed. Non-Apple
  pipeline/extension setup is unchanged.
- window: optional borderless window (KYTY_BORDERLESS) to sidestep a Rosetta
  NSException in macOS window chrome.

* graphics: macOS thread identity for region tracking

Region-ownership locks resolve the current thread via GetCurrentThreadId()
on Windows and EXIT elsewhere. Use the Mach thread port on macOS (nonzero
per-thread id; 0 stays the no-owner sentinel).

* macos: marshal AppKit window operations to the main thread

The present worker thread shows the window, updates its icon and title, and
recreates a lost Vulkan surface. AppKit traps with 'Must only be used from the
main thread' when these run off the main thread. Route them through a small
task queue drained by the SDL main loop (an SDL_USEREVENT wakes the loop when
it is blocked in SDL_WaitEvent). Title updates are fire-and-forget; showing
the window and surface recreation wait for completion.

Windows and Linux call the SDL functions directly, as before.

* build: ignore the _Build output directory

_Build is the conventional out-of-tree build location (only _Build/vscode-clang
was ignored); a stray git add could sweep build artifacts into a commit.

* macos: isolate stack-switch workaround

---------

Co-authored-by: nmzik <Nmzik@mail.ru>

src/graphics/host_gpu/renderer/renderDraw.cpp

@@ -395,6 +395,10 @@ static void SetDynamicParams(const RenderCommandBuffer& buffer, vk::CommandBuffe
 		                              dynamic_params.stencil_back.reference);
 	}
 
+#if defined(__APPLE__)
+	// MoltenVK has no VK_EXT_color_write_enable; the pipeline is created without the
+	// eColorWriteEnableEXT dynamic state and relies on the static colorWriteMask instead.
+#else
 	vk::Bool32 enable[RENDER_COLOR_ATTACHMENTS_MAX] = {};
 	for (uint32_t i = 0; i < dynamic_params.color_write_count; i++) {
 		enable[i] = (dynamic_params.color_write_enable[i] ? VK_TRUE : VK_FALSE);
@@ -402,6 +406,7 @@ static void SetDynamicParams(const RenderCommandBuffer& buffer, vk::CommandBuffe
 	if (dynamic_params.color_write_count != 0) {
 		vk_buffer.setColorWriteEnableEXT(dynamic_params.color_write_count, enable);
 	}
+#endif
 }
 
 static bool DrawHasValidVertexShader(const HW::Shader& sh_ctx) {

src/graphics/host_gpu/renderer/shaders.cpp

@@ -729,7 +729,13 @@ void CreatePipelineInternal(GraphicContext& graphics, DescriptorCache& descripto
 
 	vk::PipelineRasterizationStateCreateInfo rasterizer {};
 	rasterizer.sType                   = vk::StructureType::ePipelineRasterizationStateCreateInfo;
+	// MoltenVK lacks VK_EXT_depth_clip_enable; omit the depth-clip struct on macOS and accept
+	// Vulkan's default depth clipping (enabled) instead of the PS5's clamp behavior.
+#if defined(__APPLE__)
+	rasterizer.pNext                   = nullptr;
+#else
 	rasterizer.pNext                   = &clip_ext;
+#endif
 	rasterizer.flags                   = {};
 	rasterizer.depthClampEnable        = VK_FALSE;
 	rasterizer.rasterizerDiscardEnable = VK_FALSE;
@@ -807,7 +813,13 @@ void CreatePipelineInternal(GraphicContext& graphics, DescriptorCache& descripto
 
 	vk::PipelineColorBlendStateCreateInfo color_blending {};
 	color_blending.sType             = vk::StructureType::ePipelineColorBlendStateCreateInfo;
+	// MoltenVK lacks VK_EXT_color_write_enable; drop the dynamic color-write struct on macOS
+	// and rely on each attachment's static colorWriteMask (all channels enabled by default).
+#if defined(__APPLE__)
+	color_blending.pNext             = nullptr;
+#else
 	color_blending.pNext             = &color_write;
+#endif
 	color_blending.flags             = {};
 	color_blending.logicOpEnable     = VK_FALSE;
 	color_blending.logicOp           = vk::LogicOp::eCopy;
@@ -873,7 +885,11 @@ void CreatePipelineInternal(GraphicContext& graphics, DescriptorCache& descripto
 	depth_stencil_info.depthWriteEnable = (static_params.depth_write_enable ? VK_TRUE : VK_FALSE);
 	depth_stencil_info.depthCompareOp   = static_params.depth_compare_op;
 	depth_stencil_info.depthBoundsTestEnable =
+#if defined(__APPLE__)
+	    VK_FALSE; // MoltenVK lacks the depthBounds feature; depth-bounds testing is disabled
+#else
 	    (static_params.depth_bounds_test_enable ? VK_TRUE : VK_FALSE);
+#endif
 	depth_stencil_info.stencilTestEnable = (static_params.stencil_test_enable ? VK_TRUE : VK_FALSE);
 	depth_stencil_info.front.failOp      = static_params.stencil_front.failOp;
 	depth_stencil_info.front.passOp      = static_params.stencil_front.passOp;
@@ -893,7 +909,9 @@ void CreatePipelineInternal(GraphicContext& graphics, DescriptorCache& descripto
 	    vk::DynamicState::eStencilCompareMask,
 	    vk::DynamicState::eStencilReference,
 	    vk::DynamicState::eStencilWriteMask,
-	    vk::DynamicState::eColorWriteEnableEXT,
+#if !defined(__APPLE__)
+	    vk::DynamicState::eColorWriteEnableEXT, // unsupported by MoltenVK; static mask instead
+#endif
 	};
 	const auto dynamic_states_count =
 	    static_cast<uint32_t>(sizeof(dynamic_states) / sizeof(dynamic_states[0]));