icd: add more utils for working with floats
diff --git a/icd/common/CMakeLists.txt b/icd/common/CMakeLists.txt
index 7c8e835..ba49a23 100644
--- a/icd/common/CMakeLists.txt
+++ b/icd/common/CMakeLists.txt
@@ -9,5 +9,5 @@
DEPENDS ${PROJECT_SOURCE_DIR}/xgl-generate.py
${PROJECT_SOURCE_DIR}/xgl.py)
-add_library(icd OBJECT icd.c icd-dispatch-entrypoints.c icd-dispatch-table.h icd-format.c)
+add_library(icd OBJECT icd.c icd-dispatch-entrypoints.c icd-dispatch-table.h icd-format.c icd-utils.c)
set_target_properties(icd PROPERTIES POSITION_INDEPENDENT_CODE ON)
diff --git a/icd/common/icd-utils.c b/icd/common/icd-utils.c
new file mode 100644
index 0000000..2c0b870
--- /dev/null
+++ b/icd/common/icd-utils.c
@@ -0,0 +1,83 @@
+/*
+ * XGL
+ *
+ * Copyright (C) 2014 LunarG, Inc.
+ *
+ * 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 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 AUTHORS OR COPYRIGHT HOLDERS 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.
+ */
+
+#include "icd-utils.h"
+
+/* stolen from Mesa */
+uint16_t u_float_to_half(float f)
+{
+ union fi {
+ float f;
+ uint32_t ui;
+ };
+
+ uint32_t sign_mask = 0x80000000;
+ uint32_t round_mask = ~0xfff;
+ uint32_t f32inf = 0xff << 23;
+ uint32_t f16inf = 0x1f << 23;
+ uint32_t sign;
+ union fi magic;
+ union fi f32;
+ uint16_t f16;
+
+ magic.ui = 0xf << 23;
+
+ f32.f = f;
+
+ /* Sign */
+ sign = f32.ui & sign_mask;
+ f32.ui ^= sign;
+
+ if (f32.ui == f32inf) {
+ /* Inf */
+ f16 = 0x7c00;
+ } else if (f32.ui > f32inf) {
+ /* NaN */
+ f16 = 0x7e00;
+ } else {
+ /* Number */
+ f32.ui &= round_mask;
+ f32.f *= magic.f;
+ f32.ui -= round_mask;
+
+ /*
+ * Clamp to max finite value if overflowed.
+ * OpenGL has completely undefined rounding behavior for float to
+ * half-float conversions, and this matches what is mandated for float
+ * to fp11/fp10, which recommend round-to-nearest-finite too.
+ * (d3d10 is deeply unhappy about flushing such values to infinity, and
+ * while it also mandates round-to-zero it doesn't care nearly as much
+ * about that.)
+ */
+ if (f32.ui > f16inf)
+ f32.ui = f16inf - 1;
+
+ f16 = f32.ui >> 13;
+ }
+
+ /* Sign */
+ f16 |= sign >> 16;
+
+ return f16;
+}
diff --git a/icd/common/icd-utils.h b/icd/common/icd-utils.h
index c600852..26f911e 100644
--- a/icd/common/icd-utils.h
+++ b/icd/common/icd-utils.h
@@ -25,6 +25,8 @@
#ifndef ICD_UTILS_H
#define ICD_UTILS_H
+#include <stdbool.h>
+#include <stdint.h>
#include <assert.h>
#include "icd.h"
@@ -34,6 +36,9 @@
(void) sizeof(char[1 - 2 * !(expr)]); \
} while (0)
+#define U_CLAMP(val, min, max) \
+ ((val) < (min) ? (min) : (val) > (max)? (max) : (val))
+
/**
* Return true if val is power of two, or zero.
*/
@@ -53,4 +58,24 @@
return (val >> level) ? val >> level : 1;
}
+static inline uint32_t u_fui(float f)
+{
+ union {
+ float f;
+ uint32_t ui;
+ } u = { .f = f };
+
+ return u.ui;
+}
+
+static inline int u_iround(float f)
+{
+ if (f >= 0.0f)
+ return (int) (f + 0.5f);
+ else
+ return (int) (f - 0.5f);
+}
+
+uint16_t u_float_to_half(float f);
+
#endif /* ICD_UTILS_H */