1 files changed, 80 insertions, 0 deletions
diff --git a/gfx/angle/src/common/Float16ToFloat32.py b/gfx/angle/src/common/Float16ToFloat32.py
new file mode 100755
index 000000000..7705f7b61
--- /dev/null
+++ b/gfx/angle/src/common/Float16ToFloat32.py
@@ -0,0 +1,80 @@
+# Copyright (c) 2012 The ANGLE Project Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+#
+
+# This script generates a function that converts 16-bit precision floating
+# point numbers to 32-bit.
+# It is based on ftp://ftp.fox-toolkit.org/pub/fasthalffloatconversion.pdf.
+
+#include "common/mathutil.h"
+
+def convertMantissa(i):
+    if i == 0:
+        return 0
+    elif i < 1024:
+        m = i << 13
+        e = 0
+        while not (m & 0x00800000):
+            e -= 0x00800000
+            m = m << 1
+        m &= ~0x00800000
+        e += 0x38800000
+        return m | e
+    else:
+        return 0x38000000 + ((i - 1024) << 13)
+
+def convertExponent(i):
+    if i == 0:
+        return 0
+    elif i in range(1, 31):
+        return i << 23
+    elif i == 31:
+        return 0x47800000
+    elif i == 32:
+        return 0x80000000
+    elif i in range(33, 63):
+        return 0x80000000 + ((i - 32) << 23)
+    else:
+        return 0xC7800000
+
+def convertOffset(i):
+    if i == 0 or i == 32:
+        return 0
+    else:
+        return 1024
+
+print """//
+// Copyright (c) 2012 The ANGLE Project Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+
+// This file is automatically generated.
+
+namespace gl
+{
+"""
+
+print "const static unsigned g_mantissa[2048] = {"
+for i in range(0, 2048):
+    print "    %#010x," % convertMantissa(i)
+print "};\n"
+
+print "const static unsigned g_exponent[64] = {"
+for i in range(0, 64):
+    print "    %#010x," % convertExponent(i)
+print "};\n"
+
+print "const static unsigned g_offset[64] = {"
+for i in range(0, 64):
+    print "    %#010x," % convertOffset(i)
+print "};\n"
+
+print """float float16ToFloat32(unsigned short h)
+{
+    unsigned i32 = g_mantissa[g_offset[h >> 10] + (h & 0x3ff)] + g_exponent[h >> 10];
+    return bitCast<float>(i32);
+}
+}
+"""