py/misc: Move mp_clz and mp_ctz intrinsics into misc.h.

Signed-off-by: Angus Gratton <[email protected]>
picoscratch · Jun 24, 2024 · d933210 · d933210
1 parent cebc9b0
commit d933210
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Showing 2 changed files with 19 additions and 17 deletions.
diff --git a/py/asmthumb.c b/py/asmthumb.c
@@ -35,23 +35,7 @@
 
 #include "py/mpstate.h"
 #include "py/asmthumb.h"
-
-#ifdef _MSC_VER
-#include <intrin.h>
-
-static uint32_t mp_clz(uint32_t x) {
-    unsigned long lz = 0;
-    return _BitScanReverse(&lz, x) ? (sizeof(x) * 8 - 1) - lz : 0;
-}
-
-static uint32_t mp_ctz(uint32_t x) {
-    unsigned long tz = 0;
-    return _BitScanForward(&tz, x) ? tz : 0;
-}
-#else
-#define mp_clz(x) __builtin_clz(x)
-#define mp_ctz(x) __builtin_ctz(x)
-#endif
+#include "py/misc.h"
 
 #define UNSIGNED_FIT5(x) ((uint32_t)(x) < 32)
 #define UNSIGNED_FIT7(x) ((uint32_t)(x) < 128)

diff --git a/py/misc.h b/py/misc.h
@@ -334,4 +334,22 @@ typedef const char *mp_rom_error_text_t;
 // For now, forward directly to MP_COMPRESSED_ROM_TEXT.
 #define MP_ERROR_TEXT(x) (mp_rom_error_text_t)MP_COMPRESSED_ROM_TEXT(x)
 
+// Portable implementations of CLZ and CTZ intrinsics
+#ifdef _MSC_VER
+#include <intrin.h>
+
+static uint32_t mp_clz(uint32_t x) {
+    unsigned long lz = 0;
+    return _BitScanReverse(&lz, x) ? (sizeof(x) * 8 - 1) - lz : 0;
+}
+
+static uint32_t mp_ctz(uint32_t x) {
+    unsigned long tz = 0;
+    return _BitScanForward(&tz, x) ? tz : 0;
+}
+#else
+#define mp_clz(x) __builtin_clz(x)
+#define mp_ctz(x) __builtin_ctz(x)
+#endif
+
 #endif // MICROPY_INCLUDED_PY_MISC_H