shithub: hj264

Info  •  Files  •  Log

add clz and bswap32 builtins

--- a/builtins.amd64.s

+++ b/builtins.amd64.s

@@ -5,3 +5,13 @@

 	MOVL n+16(FP), CX

 	CLD; REP; MOVSB

 	RET

+	

+TEXT __builtin_clz(SB),1,$0

+	BYTE $0x0F; BYTE $0xBD; BYTE $0xC5 /* BSRL RARG, AX */

+	XORL $31, AX

+	RET

+

+TEXT __builtin_bswap32(SB),1,$0

+	MOVQ RARG, AX

+	BYTE $0x0F; BYTE $0xC8 /* BSWAP32 AX */

+	RET

--- a/builtins.c

+++ b/builtins.c

@@ -1,0 +1,15 @@

+int

+__builtin_clz(unsigned int x)

+{

+	unsigned int r;

+	if(x == 0)

+		return 32;

+	for(r = 0; (x & (1UL<<31)) == 0; x <<= 1, r++);

+	return r;

+}

+

+unsigned int

+__builtin_bswap32(unsigned int x)

+{

+	return ((x >> 24) & 0xff) | ((x >> 8) & 0xff00) | ((x << 8) & 0xff0000) | ((x & 0xff) << 24);

+}

--- a/hj264.c

+++ b/hj264.c

@@ -1,8 +1,6 @@

+#include "builtins.h"

 #define MINIH264_IMPLEMENTATION

 #define H264E_MAX_THREADS 7

-#ifdef __amd64__

-#define memcpy memcpyf

-#endif

 #include "minih264e.h"

 #include <thread.h>

 #include <bio.h>

--- a/minih264e.h

+++ b/minih264e.h

@@ -8111,6 +8111,9 @@

 /************************************************************************/

 #ifndef __arm__

+#if defined(__GNUC__) || defined(__clang__) || defined(__aarch64__)

+#define __clz(v) __builtin_clz(v)

+#else

 /**

 *   Count of leading zeroes

 */

@@ -8120,8 +8123,6 @@

     unsigned long nbit;

     _BitScanReverse(&nbit, v);

     return 31 - nbit;

-#elif defined(__GNUC__) || defined(__clang__) || defined(__aarch64__)

-    return __builtin_clz(v);

 #else

     unsigned clz = 32;

     assert(v);

@@ -8132,6 +8133,7 @@

     return clz;

 #endif

 }

+#endif

 #endif

 /**

--- a/mkfile

+++ b/mkfile

@@ -1,6 +1,6 @@

 </$objtype/mkfile

-CFLAGS=$CFLAGS -p -I/sys/include/npe -D__plan9__ -D__${objtype}__

+CFLAGS=$CFLAGS -p -I/sys/include/npe -D__plan9__ -D__${objtype}__ -D__clang__

 BIN=/$objtype/bin/video

 TARG=hj264