msvcp90: Add std:_XLgamma implementation.

dlls/msvcp100/msvcp100.spec

@@ -1260,9 +1260,9 @@
 @ cdecl -arch=win64 ?_Unlock@?$basic_streambuf@_WU?$char_traits@_W@std@@@std@@UEAAXXZ(ptr) basic_streambuf_wchar__Unlock
 @ thiscall -arch=win32 ?_Unlock@_Mutex@std@@QAEXXZ(ptr) mutex_unlock
 @ cdecl -arch=win64 ?_Unlock@_Mutex@std@@QEAAXXZ(ptr) mutex_unlock
-@ stub ?_XLgamma@tr1@std@@YAMM@Z
-@ stub ?_XLgamma@tr1@std@@YANN@Z
-@ stub ?_XLgamma@tr1@std@@YAOO@Z
+@ cdecl ?_XLgamma@tr1@std@@YAMM@Z(float) std__XLgamma_float
+@ cdecl ?_XLgamma@tr1@std@@YANN@Z(double) std__XLgamma_double
+@ cdecl ?_XLgamma@tr1@std@@YAOO@Z(double) std__XLgamma_double
 @ stub ?_Xbad@tr1@std@@YAXW4error_type@regex_constants@12@@Z
 @ stub ?_Xfunc@tr1@std@@YAXXZ
 @ cdecl -arch=win32 ?_Xinvalid_argument@std@@YAXPBD@Z(str) _Xinvalid_argument

dlls/msvcp110/msvcp110.spec

@@ -1829,9 +1829,9 @@
 @ stub -arch=win64 ?_W_Gettnames@_Locinfo@std@@QEBA?AV_Timevec@2@XZ
 @ stub -arch=win32 ?_Winerror_map@std@@YAPBDH@Z
 @ stub -arch=win64 ?_Winerror_map@std@@YAPEBDH@Z
-@ stub ?_XLgamma@std@@YAMM@Z
-@ stub ?_XLgamma@std@@YANN@Z
-@ stub ?_XLgamma@std@@YAOO@Z
+@ cdecl ?_XLgamma@std@@YAMM@Z(float) std__XLgamma_float
+@ cdecl ?_XLgamma@std@@YANN@Z(double) std__XLgamma_double
+@ cdecl ?_XLgamma@std@@YAOO@Z(double) std__XLgamma_double
 @ cdecl ?_Xbad_alloc@std@@YAXXZ() _Xmem
 @ stub ?_Xbad_function_call@std@@YAXXZ
 @ cdecl -arch=win32 ?_Xinvalid_argument@std@@YAXPBD@Z(str) _Xinvalid_argument

dlls/msvcp120/msvcp120.spec

@@ -1790,9 +1790,9 @@
 @ stub -arch=win64 ?_W_Gettnames@_Locinfo@std@@QEBA?AV_Timevec@2@XZ
 @ stub -arch=win32 ?_Winerror_map@std@@YAPBDH@Z
 @ stub -arch=win64 ?_Winerror_map@std@@YAPEBDH@Z
-@ stub ?_XLgamma@std@@YAMM@Z
-@ stub ?_XLgamma@std@@YANN@Z
-@ stub ?_XLgamma@std@@YAOO@Z
+@ cdecl ?_XLgamma@std@@YAMM@Z(float) std__XLgamma_float
+@ cdecl ?_XLgamma@std@@YANN@Z(double) std__XLgamma_double
+@ cdecl ?_XLgamma@std@@YAOO@Z(double) std__XLgamma_double
 @ cdecl ?_Xbad_alloc@std@@YAXXZ() _Xmem
 @ stub ?_Xbad_function_call@std@@YAXXZ
 @ cdecl -arch=win32 ?_Xinvalid_argument@std@@YAXPBD@Z(str) _Xinvalid_argument

dlls/msvcp120_app/msvcp120_app.spec

@@ -1790,9 +1790,9 @@
 @ stub -arch=win64 ?_W_Gettnames@_Locinfo@std@@QEBA?AV_Timevec@2@XZ
 @ stub -arch=win32 ?_Winerror_map@std@@YAPBDH@Z
 @ stub -arch=win64 ?_Winerror_map@std@@YAPEBDH@Z
-@ stub ?_XLgamma@std@@YAMM@Z
-@ stub ?_XLgamma@std@@YANN@Z
-@ stub ?_XLgamma@std@@YAOO@Z
+@ cdecl ?_XLgamma@std@@YAMM@Z(float) msvcp120.?_XLgamma@std@@YAMM@Z
+@ cdecl ?_XLgamma@std@@YANN@Z(double) msvcp120.?_XLgamma@std@@YANN@Z
+@ cdecl ?_XLgamma@std@@YAOO@Z(double) msvcp120.?_XLgamma@std@@YAOO@Z
 @ cdecl ?_Xbad_alloc@std@@YAXXZ() msvcp120.?_Xbad_alloc@std@@YAXXZ
 @ stub ?_Xbad_function_call@std@@YAXXZ
 @ cdecl -arch=win32 ?_Xinvalid_argument@std@@YAXPBD@Z(str) msvcp120.?_Xinvalid_argument@std@@YAXPBD@Z

dlls/msvcp140/msvcp140.spec

@@ -1673,9 +1673,9 @@
 @ cdecl -arch=win32 ?_Winerror_message@std@@YAKKPADK@Z(long ptr long) _Winerror_message
 @ cdecl -arch=win64 ?_Winerror_message@std@@YAKKPEADK@Z(long ptr long) _Winerror_message
 @ stub ?_XGetLastError@std@@YAXXZ
-@ stub ?_XLgamma@std@@YAMM@Z
-@ stub ?_XLgamma@std@@YANN@Z
-@ stub ?_XLgamma@std@@YAOO@Z
+@ cdecl ?_XLgamma@std@@YAMM@Z(float) std__XLgamma_float
+@ cdecl ?_XLgamma@std@@YANN@Z(double) std__XLgamma_double
+@ cdecl ?_XLgamma@std@@YAOO@Z(double) std__XLgamma_double
 @ cdecl ?_Xbad_alloc@std@@YAXXZ() _Xmem
 @ stub ?_Xbad_function_call@std@@YAXXZ
 @ cdecl -arch=win32 ?_Xinvalid_argument@std@@YAXPBD@Z(str) _Xinvalid_argument

dlls/msvcp90/math.c

@@ -2362,3 +2362,36 @@ short __cdecl _FExp(float *x, float y, short scale)
 
     return dclass(*x);
 }
+
+/* ?_XLgamma@std@@YANN@Z */
+double __cdecl std__XLgamma_double(double z)
+{
+    /* Lanczos coefficients g=5, n=6 */
+    static const double lc[] = {
+        1.000000000190015,
+        76.18009172947146,
+        -86.50532032941677,
+        24.01409824083091,
+        -1.231739572450155,
+        0.1208650973866179e-2,
+        -0.5395239384953e-5
+    };
+    static const double log_sqrt_2pi = 0.91893853320467274178;
+
+    double base = z + 4.5, sum = 0;
+    int i;
+
+    if (z < 0.5) return log(M_PI / sin(M_PI * z)) - std__XLgamma_double(1 - z);
+
+    z--;
+    for(i = ARRAY_SIZE(lc) - 1; i >= 1; i--)
+        sum += lc[i] / (z + i);
+    sum += lc[0];
+    return log_sqrt_2pi + log(sum) - base + log(base) * (z + 0.5);
+}
+
+/* ?_XLgamma@tr1@std@@YAMM@Z */
+float __cdecl std__XLgamma_float(float z)
+{
+    return std__XLgamma_double(z);
+}

dlls/msvcp90/msvcp90.spec

@@ -3185,9 +3185,9 @@
 @ cdecl -arch=win64 ?_Widen_s@?$ctype@G@std@@QEBAPEBDPEBD0PEAG_K@Z(ptr ptr ptr ptr long) ctype_wchar__Widen_s
 @ thiscall -arch=win32 ?_Widen_s@?$ctype@_W@std@@QBEPBDPBD0PA_WI@Z(ptr ptr ptr ptr long) ctype_wchar__Widen_s
 @ cdecl -arch=win64 ?_Widen_s@?$ctype@_W@std@@QEBAPEBDPEBD0PEA_W_K@Z(ptr ptr ptr ptr long) ctype_wchar__Widen_s
-@ stub ?_XLgamma@tr1@std@@YAMM@Z
-@ stub ?_XLgamma@tr1@std@@YANN@Z
-@ stub ?_XLgamma@tr1@std@@YAOO@Z
+@ cdecl ?_XLgamma@tr1@std@@YAMM@Z(float) std__XLgamma_float
+@ cdecl ?_XLgamma@tr1@std@@YANN@Z(double) std__XLgamma_double
+@ cdecl ?_XLgamma@tr1@std@@YAOO@Z(double) std__XLgamma_double
 @ stub ?_Xbad@tr1@std@@YAXW4error_type@regex_constants@12@@Z
 @ stub -arch=win32 ?_Xfsopen@std@@YAPAU_iobuf@@PB_W0H@Z
 @ stub -arch=win64 ?_Xfsopen@std@@YAPEAU_iobuf@@PEB_W0H@Z