msvcr110: Add __crtCapturePreviousContext implementation.

dlls/msvcr110/msvcr110.spec

@@ -905,7 +905,7 @@
 @ cdecl -arch=i386 __control87_2(long long ptr ptr)
 @ cdecl __create_locale(long str) MSVCRT__create_locale
 @ cdecl -arch=win64 -norelay __crtCaptureCurrentContext(ptr) ntdll.RtlCaptureContext
-@ stub -arch=win64 __crtCapturePreviousContext
+@ cdecl -arch=x86_64 -norelay __crtCapturePreviousContext(ptr)
 @ cdecl __crtCompareStringA(long long str long str long)
 @ stub -arch=i386,win64 __crtCompareStringEx
 @ cdecl __crtCompareStringW(long long wstr long wstr long)

dlls/msvcr120/msvcr120.spec

@@ -890,7 +890,7 @@
 @ cdecl -arch=i386 __control87_2(long long ptr ptr)
 @ cdecl __create_locale(long str) MSVCRT__create_locale
 @ cdecl -arch=win64 -norelay __crtCaptureCurrentContext(ptr) ntdll.RtlCaptureContext
-@ stub -arch=win64 __crtCapturePreviousContext
+@ cdecl -arch=x86_64 -norelay __crtCapturePreviousContext(ptr)
 @ cdecl __crtCompareStringA(long long str long str long)
 @ stub -arch=i386,win64 __crtCompareStringEx
 @ cdecl __crtCompareStringW(long long wstr long wstr long)

dlls/msvcr120_app/msvcr120_app.spec

@@ -884,7 +884,7 @@
 @ cdecl -arch=i386 __control87_2(long long ptr ptr) msvcr120.__control87_2
 @ cdecl __create_locale(long str) msvcr120.__create_locale
 @ cdecl -arch=win64 -norelay __crtCaptureCurrentContext(ptr) msvcr120.__crtCaptureCurrentContext
-@ stub -arch=win64 __crtCapturePreviousContext
+@ cdecl -arch=x86_64 -norelay __crtCapturePreviousContext(ptr) msvcr120.__crtCapturePreviousContext
 @ stub __crtCloseWinRTThreadHandle
 @ cdecl __crtCompareStringA(long long str long str long) msvcr120.__crtCompareStringA
 @ cdecl __crtCompareStringW(long long wstr long wstr long) msvcr120.__crtCompareStringW

dlls/msvcrt/except_x86_64.c

@@ -798,4 +798,42 @@ int __cdecl _fpieee_flt(ULONG exception_code, EXCEPTION_POINTERS *ep,
     return EXCEPTION_CONTINUE_SEARCH;
 }
 
+#if _MSVCR_VER>=110 && _MSVCR_VER<=120
+/*********************************************************************
+ *  __crtCapturePreviousContext (MSVCR110.@)
+ */
+void __cdecl get_prev_context(CONTEXT *ctx, DWORD64 rip)
+{
+    ULONG64 frame, image_base;
+    RUNTIME_FUNCTION *rf;
+    void *data;
+
+    TRACE("(%p)\n", ctx);
+
+    ctx->Rip = rip;
+    ctx->Rsp += 3*8; /* Rip, Rcx, return address */
+
+    rf = RtlLookupFunctionEntry(ctx->Rip, &image_base, NULL);
+    if(!rf) {
+        FIXME("RtlLookupFunctionEntry failed\n");
+        return;
+    }
+
+    RtlVirtualUnwind(UNW_FLAG_NHANDLER, image_base, ctx->Rip,
+            rf, ctx, &data, &frame, NULL);
+}
+
+__ASM_GLOBAL_FUNC( __crtCapturePreviousContext,
+        "pushq (%rsp)\n\t" /* save Rip */
+        __ASM_CFI(".cfi_adjust_cfa_offset 8\n\t")
+        "pushq %rcx\n\t"
+        __ASM_CFI(".cfi_adjust_cfa_offset 8\n\t")
+        "call " __ASM_NAME("RtlCaptureContext") "\n\t"
+        "popq %rcx\n\t"
+        __ASM_CFI(".cfi_adjust_cfa_offset -8\n\t")
+        "popq %rdx\n\t"
+        __ASM_CFI(".cfi_adjust_cfa_offset -8\n\t")
+        "jmp " __ASM_NAME("get_prev_context") );
+#endif
+
 #endif  /* __x86_64__ */