[*] Initial commit

lonetix/bgp/vm_gccdef.h

@@ -0,0 +1,66 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+
+/**
+ * \file bgp/vm_gccdef.h
+ *
+ * `#define`s for GNUC optimized BGP VM execution loop.
+ *
+ * \copyright The DoubleFourteen Code Forge (C) All Rights Reserved
+ * \author    Lorenzo Cogotti
+ *
+ * \note This file should be `#include`d by `bgp/vm.c`
+ */
+
+#ifdef DF_BGP_VMDEF_H_
+#error "Only one vm_<impl>def.h file may be #include-d"
+#endif
+#define DF_BGP_VMDEF_H_
+
+#define _CONCAT(x, y)  x ## y
+#define _XCONCAT(x, y) _CONCAT(x, y)
+
+#ifdef __clang__
+// No __attribute__ on labels in CLANG
+#define LIKELY
+#else
+
+#define LIKELY \
+	_XCONCAT(_BRANCH_PREDICT_HINT, __COUNTER__): \
+	__attribute__((__hot__, __unused__))
+
+#endif
+
+#ifdef __clang__
+// No __attribute__ on labels in CLANG
+#define UNLIKELY
+#else
+
+#define UNLIKELY \
+	_XCONCAT(_BRANCH_PREDICT_HINT, __COUNTER__): \
+	__attribute__((__cold__, __unused__))
+
+#endif
+
+#define FETCH(ir, vm) (ir = (vm)->prog[(vm)->pc++])
+
+#define EXPECT(opcode, ir, vm) \
+	do { \
+		if (__builtin_expect( \
+			BGP_VMOPC((vm)->prog[(vm)->pc]) == BGP_VMOP_ ## opcode, \
+			1                                                       \
+		)) { \
+			ir = (vm)->prog[(vm)->pc++]; \
+			goto EX_ ## opcode;          \
+		} \
+	} while (0)
+
+#define DISPATCH(opcode) \
+	_Pragma("GCC diagnostic push");                  \
+	_Pragma("GCC diagnostic ignored \"-Wpedantic\"") \
+	goto *bgp_vmOpTab[opcode];                       \
+	_Pragma("GCC diagnostic pop")                    \
+	switch (opcode)  // This keeps consistency with regular vm_cdef.h
+
+#define EXECUTE(opcode) case BGP_VMOP_ ## opcode: EX_ ## opcode
+
+#define EXECUTE_SIGILL default: EX_SIGILL