mmh

Author: imaami

src/Makefile

@@ -1,6 +1,6 @@
 override THIS_DIR := $(dir $(realpath $(lastword $(MAKEFILE_LIST))))
 
-override TARGETS := stochar test test-json test-utf8
+override TARGETS := stochar test test-json test-rev test-utf8
 
     all:| $(TARGETS)
   clean:| $(TARGETS:%=clean-%)
@@ -26,6 +26,8 @@ override DBG_test := dbg.c
 override LIBS_test = $(CJSON_LIBS)
 override CFLAGS_test.c = $(CJSON_CFLAGS)
 
+override SRC_test-rev := parse.c test-rev.c
+
 override SRC_test-json := json.c test-json.c
 override DBG_test-json := dbg.c
 

src/rev.h

@@ -20,28 +20,28 @@ typedef unsigned _BitInt(2) uint2;
 typedef unsigned _BitInt(4) uint4;
 #define uint2(x) (uint2)(x)
 #define uint4(x) (uint4)(x)
-#define uint2_get(x) x
-#define uint4_get(x) x
+#define uint2_get(x) (x)
+#define uint4_get(x) (x)
 #endif
 
 static const_inline uint2
 rev2 (uint2 x)
 {
-	x ^= (x & 0x2) >> 1U;
-	x ^= (x & 0x1) << 1U;
-	x ^= (x & 0x2) >> 1U;
+	uint2_get(x) ^= (uint2_get(x) & 0x2U) >> 1U;
+	uint2_get(x) ^= (uint2_get(x) & 0x1U) << 1U;
+	uint2_get(x) ^= (uint2_get(x) & 0x2U) >> 1U;
 	return x;
 }
 
 static const_inline uint4
 rev4 (uint4 x)
 {
-	x ^= (x & 0xa) >> 1U;
-	x ^= (x & 0x5) << 1U;
-	x ^= (x & 0xc) >> 2U;
-	x ^= (x & 0x3) << 2U;
-	x ^= (x & 0xc) >> 2U;
-	x ^= (x & 0xa) >> 1U;
+	uint4_get(x) ^= (uint4_get(x) & 0xaU) >> 1U;
+	uint4_get(x) ^= (uint4_get(x) & 0x5U) << 1U;
+	uint4_get(x) ^= (uint4_get(x) & 0xcU) >> 2U;
+	uint4_get(x) ^= (uint4_get(x) & 0x3U) << 2U;
+	uint4_get(x) ^= (uint4_get(x) & 0xcU) >> 2U;
+	uint4_get(x) ^= (uint4_get(x) & 0xaU) >> 1U;
 	return x;
 }
 

src/test-rev.c

@@ -9,16 +9,79 @@
 #include "parse.h"
 #include "rev.h"
 
+struct asc4 {
+	char d[4];
+};
+
+__attribute__((const))
+static struct asc4
+bin_asc (uint4 x)
+{
+
+	union {
+		char          c[35U];
+		unsigned char u[35U];
+	} const t = {
+		"1111000010011010" "111"
+		"\x04""\x05""\x06"
+		"\x09""\x07""\x0d"
+		"\x0a""\x0f""\x03"
+		"\x08""\x0c""\x0e"
+		"\x02""\x0b""\x01"
+	};
+	unsigned const i = t.u[
+		19U + uint4_get(x)
+	];
+	return (struct asc4){ .d = {
+		t.c[i+0U], t.c[i+1U],
+		t.c[i+2U], t.c[i+3U]
+	}};
+}
+
 int
 main (int    c,
       char **v)
 {
 	for (int i = 0; ++i < c;) {
 		struct parsed p = parse_u64(v[i]);
-		if (parsed_ok(p, v[i]))
-			(void)printf("%016" PRIx64 " "
-			             "%016" PRIx64 "\n",
-			             p.u64, rev64(p.u64));
+		if (!parsed_ok(p, v[i]))
+			continue;
+
+		(void)printf("%016" PRIx64 " "
+		             "%016" PRIx64 "\n",
+		             p.u64, rev64(p.u64));
+
+		if (p.u64 > UINT32_MAX)
+			continue;
+		(void)printf("        %0"
+		             "8" PRIx64 " "
+		             "%08" PRIx32 "\n",
+		             p.u64, rev32((uint32_t)p.u64));
+
+		if (p.u64 > UINT16_MAX)
+			continue;
+		(void)printf("            %0"
+		             "4" PRIx64 " "
+		             "%04" PRIx16 "\n",
+		             p.u64, rev16((uint16_t)p.u64));
+
+		if (p.u64 > UINT8_MAX)
+			continue;
+		(void)printf("              %0"
+		             "2" PRIx64 " "
+		             "%02" PRIx8 "\n",
+		             p.u64, rev8((uint8_t)p.u64));
+
+		if (p.u64 > 15U)
+			continue;
+		(void)printf("               "
+		             "%" PRIx64 " %x\n",
+		             p.u64, (unsigned)uint4_get(rev4(uint4(p.u64))));
 
+		if (p.u64 > 3U)
+			continue;
+		(void)printf("               "
+		             "%" PRIx64 " %x\n",
+		             p.u64, (unsigned)uint2_get(rev2(uint2(p.u64))));
 	}
 }