mesa,glsl: Move round_to_even() from glsl to mesa/main (v2)

Move round_to_even's definition to mesa/main so that _mesa_float_to_half()
can use it in order to eliminate rounding bias.

In additon to moving the fuction definition, prefix its name with "_mesa",
just as all other functions in mesa/main are prefixed.

v2: Fix Android build.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Signed-off-by: Chad Versace <chad.versace@linux.intel.com>
diff --git a/src/glsl/Makefile.am b/src/glsl/Makefile.am
index 058d8ae..d0e5cd1 100644
--- a/src/glsl/Makefile.am
+++ b/src/glsl/Makefile.am
@@ -52,6 +52,7 @@
 
 tests_uniform_initializer_test_SOURCES =		\
 	$(top_srcdir)/src/mesa/main/hash_table.c	\
+	$(top_srcdir)/src/mesa/main/imports.c		\
 	$(top_srcdir)/src/mesa/program/prog_hash_table.c\
 	$(top_srcdir)/src/mesa/program/symbol_table.c	\
 	tests/copy_constant_to_storage_tests.cpp	\
@@ -100,6 +101,7 @@
 
 glsl_test_SOURCES = \
 	$(top_srcdir)/src/mesa/main/hash_table.c \
+	$(top_srcdir)/src/mesa/main/imports.c \
 	$(top_srcdir)/src/mesa/program/prog_hash_table.c \
 	$(top_srcdir)/src/mesa/program/symbol_table.c \
 	$(GLSL_SRCDIR)/standalone_scaffolding.cpp \
diff --git a/src/glsl/builtin_compiler/Makefile.am b/src/glsl/builtin_compiler/Makefile.am
index 1a863b2..9766408 100644
--- a/src/glsl/builtin_compiler/Makefile.am
+++ b/src/glsl/builtin_compiler/Makefile.am
@@ -55,6 +55,7 @@
 
 builtin_compiler_SOURCES = \
 	$(top_srcdir)/src/mesa/main/hash_table.c	\
+	$(top_srcdir)/src/mesa/main/imports.c		\
 	$(top_srcdir)/src/mesa/program/prog_hash_table.c\
 	$(top_srcdir)/src/mesa/program/symbol_table.c	\
 	$(BUILTIN_COMPILER_CXX_FILES)			\
diff --git a/src/glsl/ir_constant_expression.cpp b/src/glsl/ir_constant_expression.cpp
index 17b54b9..7678090 100644
--- a/src/glsl/ir_constant_expression.cpp
+++ b/src/glsl/ir_constant_expression.cpp
@@ -40,25 +40,6 @@
 #include "glsl_types.h"
 #include "program/hash_table.h"
 
-/* Using C99 rounding functions for roundToEven() implementation is
- * difficult, because round(), rint, and nearbyint() are affected by
- * fesetenv(), which the application may have done for its own
- * purposes.  Mesa's IROUND macro is close to what we want, but it
- * rounds away from 0 on n + 0.5.
- */
-static int
-round_to_even(float val)
-{
-   int rounded = IROUND(val);
-
-   if (val - floor(val) == 0.5) {
-      if (rounded % 2 != 0)
-	 rounded += val > 0 ? -1 : 1;
-   }
-
-   return rounded;
-}
-
 static float
 dot(ir_constant *op0, ir_constant *op1)
 {
@@ -279,7 +260,7 @@
    case ir_unop_round_even:
       assert(op[0]->type->base_type == GLSL_TYPE_FLOAT);
       for (unsigned c = 0; c < op[0]->type->components(); c++) {
-	 data.f[c] = round_to_even(op[0]->value.f[c]);
+	 data.f[c] = _mesa_round_to_even(op[0]->value.f[c]);
       }
       break;
 
diff --git a/src/mesa/Android.libmesa_glsl_utils.mk b/src/mesa/Android.libmesa_glsl_utils.mk
index 9c5f349..47f2e15 100644
--- a/src/mesa/Android.libmesa_glsl_utils.mk
+++ b/src/mesa/Android.libmesa_glsl_utils.mk
@@ -35,10 +35,13 @@
 
 LOCAL_MODULE := libmesa_glsl_utils
 
-LOCAL_C_INCLUDES := $(MESA_TOP)/src/glsl
+LOCAL_C_INCLUDES := \
+	$(MESA_TOP)/src/glsl \
+	$(MESA_TOP)/src/mapi
 
 LOCAL_SRC_FILES := \
 	main/hash_table.c \
+	main/imports.c \
 	program/prog_hash_table.c \
 	program/symbol_table.c
 
@@ -54,10 +57,13 @@
 LOCAL_MODULE := libmesa_glsl_utils
 LOCAL_IS_HOST_MODULE := true
 
-LOCAL_C_INCLUDES := $(MESA_TOP)/src/glsl
+LOCAL_C_INCLUDES := \
+	$(MESA_TOP)/src/glsl \
+	$(MESA_TOP)/src/mapi
 
 LOCAL_SRC_FILES := \
 	main/hash_table.c \
+	main/imports.c \
 	program/prog_hash_table.c \
 	program/symbol_table.c
 
diff --git a/src/mesa/main/imports.c b/src/mesa/main/imports.c
index 76f835e..26c91dc 100644
--- a/src/mesa/main/imports.c
+++ b/src/mesa/main/imports.c
@@ -314,6 +314,26 @@
 #endif
 
 
+/* Using C99 rounding functions for roundToEven() implementation is
+ * difficult, because round(), rint, and nearbyint() are affected by
+ * fesetenv(), which the application may have done for its own
+ * purposes.  Mesa's IROUND macro is close to what we want, but it
+ * rounds away from 0 on n + 0.5.
+ */
+int
+_mesa_round_to_even(float val)
+{
+   int rounded = IROUND(val);
+
+   if (val - floor(val) == 0.5) {
+      if (rounded % 2 != 0)
+         rounded += val > 0 ? -1 : 1;
+   }
+
+   return rounded;
+}
+
+
 /**
  * Convert a 4-byte float to a 2-byte half float.
  * Based on code from:
diff --git a/src/mesa/main/imports.h b/src/mesa/main/imports.h
index 8446ea2..4b78381 100644
--- a/src/mesa/main/imports.h
+++ b/src/mesa/main/imports.h
@@ -548,6 +548,9 @@
 #endif
 }
 
+extern int
+_mesa_round_to_even(float val);
+
 extern GLhalfARB
 _mesa_float_to_half(float f);