Add Clang Vector Extension and swich to xyzw quat

[jopadan]

• use ext_vector_type for -DCMAKE_C_COMPILER=clang
• pass vector argument as static instance of type not address (they are all const anyway)
• use xyzw components instead of wxyz for quat
• add [src/]CMakeFiles to .gitignore

TODO

• Assert Gyro Gamepad functioning as before (I was not able to get a Gyro capable device)

DONE

• build/run with gcc/clang
• assert non-gyro gamepad function

[fabiangreffrath]

Thank you very much for your contribution! While it looks very interesting and promising, I am not sure which changes are really required and which may just be considered drive-by (i.e. the change to C23).

[gendlin]

Would now be a good time to start compiling with -ffast-math?

[fabiangreffrath]

I think you should move the feature check to the build system like this:

woof/CMakeLists.txt

Lines 68 to 77 in e832180

	check_c_source_compiles("
	#include <immintrin.h>
	int main()
	{
	int tmp = _div64(4, 2, NULL);
	return 0;
	}
	"
	HAVE__DIV64
	)

[rfomin]

Would now be a good time to start compiling with -ffast-math?

I think we still have too few float calculations.

[fabiangreffrath]

I think you should move the feature check to the build system like this:

Could you please apply something like this (untested) and see if it works for you?

--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -75,6 +75,16 @@ check_c_source_compiles("
   "
   HAVE__DIV64
 )
+check_c_source_compiles("
+    typedef float vec __attribute__((ext_vector_type(4)));
+    int main()
+    {
+        vec a = (vec){0, 1, 2, 3};
+        return 0;
+    }
+  "
+  HAVE_EXT_VECTOR_TYPE
+)

 option(CMAKE_FIND_PACKAGE_PREFER_CONFIG
        "Lookup package config files before using find modules" ON)
--- a/src/m_vector.h
+++ b/src/m_vector.h
@@ -20,9 +20,10 @@

 #include <math.h>

+#include "config.h"
 #include "doomtype.h"

-#if defined(__has_attribute) && defined(__clang__) && __has_attribute(ext_vector_type)
+#if defined(HAVE_EXT_VECTOR_TYPE)
 typedef float vec __attribute__((ext_vector_type(3)));
 #else
 typedef struct
@@ -33,7 +34,7 @@ typedef struct
 } vec;
 #endif

-#if defined(__has_attribute) && defined(__clang__) && __has_attribute(ext_vector_type)
+#if defined(HAVE_EXT_VECTOR_TYPE)
 typedef float quat __attribute__((ext_vector_type(4)));
 #else
 typedef struct

[fabiangreffrath]

LGTM, I don't care that much about the .gitignore changes.

[ceski-1]

LGTM

[rfomin]

Thanks!