Revert "util: Init half-float tables on demand."

This reverts commit 950300eb255f0e3507bf2757d16c3b5bc8ff3471.

3 files changed, 57 insertions, 14 deletions

diff --git a/src/gallium/auxiliary/util/u_half.c b/src/gallium/auxiliary/util/u_half.c
index 64eaa00dcc..4611b201b9 100644
--- a/src/gallium/auxiliary/util/u_half.c
+++ b/src/gallium/auxiliary/util/u_half.c
@@ -50,6 +50,7 @@
  */
 
 #include "util/u_half.h"
+#include "util/u_init.h"
 
 uint32_t util_half_to_float_mantissa_table[2048];
 uint32_t util_half_to_float_exponent_table[64];
@@ -57,15 +58,10 @@ uint32_t util_half_to_float_offset_table[64];
 uint16_t util_float_to_half_base_table[512];
 uint8_t util_float_to_half_shift_table[512];
 
-void util_half_init_tables(void)
+static void util_half_init_tables(void)
 {
-    static boolean inited = FALSE;
 	int i;
 
-    if (inited) {
-        return;
-    }
-
 	/* zero */
 	util_half_to_float_mantissa_table[0] = 0;
 
@@ -157,6 +153,6 @@ void util_half_init_tables(void)
 		util_float_to_half_base_table[256 + i] = util_float_to_half_base_table[i] | 0x8000;
 		util_float_to_half_shift_table[256 + i] = util_float_to_half_shift_table[i];
 	}
-
-    inited = TRUE;
 }
+
+UTIL_INIT(util_half_init_tables);
diff --git a/src/gallium/auxiliary/util/u_half.h b/src/gallium/auxiliary/util/u_half.h
index 50948cadf5..5afdd925a6 100644
--- a/src/gallium/auxiliary/util/u_half.h
+++ b/src/gallium/auxiliary/util/u_half.h
@@ -8,14 +8,13 @@
 extern "C" {
 #endif
 
+
 extern uint32_t util_half_to_float_mantissa_table[2048];
 extern uint32_t util_half_to_float_exponent_table[64];
 extern uint32_t util_half_to_float_offset_table[64];
 extern uint16_t util_float_to_half_base_table[512];
 extern uint8_t util_float_to_half_shift_table[512];
 
-void util_half_init_tables(void);
-
 /*
  * Note that if the half float is a signaling NaN, the x87 FPU will turn
  * it into a quiet NaN immediately upon loading into a float.
@@ -31,7 +30,6 @@ static INLINE uint32_t
 util_half_to_floatui(half h)
 {
 	unsigned exp = h >> 10;
-    util_half_init_tables();
 	return util_half_to_float_mantissa_table[util_half_to_float_offset_table[exp] + (h & 0x3ff)]
 		+ util_half_to_float_exponent_table[exp];
 }
@@ -40,7 +38,6 @@ static INLINE float
 util_half_to_float(half h)
 {
 	union fi r;
-    util_half_init_tables();
 	r.ui = util_half_to_floatui(h);
 	return r.f;
 }
@@ -49,7 +46,6 @@ static INLINE half
 util_floatui_to_half(uint32_t v)
 {
 	unsigned signexp = v >> 23;
-    util_half_init_tables();
 	return util_float_to_half_base_table[signexp]
 		+ ((v & 0x007fffff) >> util_float_to_half_shift_table[signexp]);
 }
@@ -58,7 +54,6 @@ static INLINE half
 util_float_to_half(float f)
 {
 	union fi i;
-    util_half_init_tables();
 	i.f = f;
 	return util_floatui_to_half(i.ui);
 }
diff --git a/src/gallium/auxiliary/util/u_init.h b/src/gallium/auxiliary/util/u_init.h
new file mode 100644
index 0000000000..40dafadf97
--- /dev/null
+++ b/src/gallium/auxiliary/util/u_init.h
@@ -0,0 +1,52 @@
+/*
+ * Copyright 2010 Luca Barbieri
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial
+ * portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ **************************************************************************/
+
+#ifndef U_INIT_H
+#define U_INIT_H
+
+/* Use UTIL_INIT(f) to have f called at program initialization.
+   Note that it is only guaranteed to be called if any symbol in the
+   .c file it is in sis referenced by the program.
+
+   UTIL_INIT functions are called in arbitrary order.
+*/
+
+#ifdef __cplusplus
+/* use a C++ global constructor */
+#define UTIL_INIT(f) struct f##__gctor_t {f##__gctor_t() {x();}} f##__gctor;
+#elif defined(_MSC_VER)
+/* add a pointer to the section where MSVC stores global constructor pointers */
+/* see http://blogs.msdn.com/vcblog/archive/2006/10/20/crt-initialization.aspx and
+   http://stackoverflow.com/questions/1113409/attribute-constructor-equivalent-in-vc */
+#pragma data_seg(".CRT$XCU")
+#define UTIL_INIT(f) static void __cdecl f##__init(void) {f();}; __declspec(allocate(".CRT$XCU")) void (__cdecl* f##__xcu)(void) = f##__init;
+#elif defined(__GNUC__)
+#define UTIL_INIT(f) static void f##__init(void) __attribute__((constructor)); static void f##__init(void) {f();}
+#else
+#error Unsupported compiler: please find out how to implement global initializers in C on it
+#endif
+
+#endif
+