lib: Add halffloat implementation

Probe for and make an API available for tests to use f16c intrinsics to
generate needed fp16 pixel data.

Also import a pure c fp32 <-> fp16 conversion implementation from Mesa
18.3.4, which will act as a fallback when f16c is unavailable.

rfc2:
- Change API to reduce number of function calls (Maarten)

v1:
- Move pragma so AVX code isn't emitted for fallbacks (Ville)
- Change edx to ecx (Ville)

Signed-off-by: Kevin Strasser <kevin.strasser@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/lib/igt_halffloat.h b/lib/igt_halffloat.h
new file mode 100644
index 00000000..8db448a1
--- /dev/null
+++ b/lib/igt_halffloat.h
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
+ *
+ * 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 <stdint.h>
+
+void igt_float_to_half(const float *f, uint16_t *h, unsigned int num);
+void igt_half_to_float(const uint16_t *h, float *f, unsigned int num);
+