Merge pull request #26 from yonik/MSVC_ctzl_fix

fix buggy use of 32 bit ctzl that resulted in crashes with recent MSVC

Author: lemire

include/boolarray.h

@@ -16,7 +16,7 @@ using namespace std;
 static inline int numberOfTrailingZeros(uint64_t x) {
   if (x == 0)
     return 64;
-  return __builtin_ctzl(x);
+  return __builtin_ctzll(x);
 }
 
 class BoolArray {
@@ -90,7 +90,7 @@ class BoolArray {
     for (uint32_t k = 0; k < buffer.size(); ++k) {
       uint64_t myword = buffer[k];
       while (myword != 0) {
-        int ntz = __builtin_ctzl(myword);
+        int ntz = __builtin_ctzll(myword);
         ans[pos++] = k * 64 + ntz;
         myword ^= (1ll << ntz);
       }

include/platform.h

@@ -22,17 +22,19 @@
 #ifdef _MSC_VER
 #include <intrin.h>
 
-uint32_t __inline __builtin_clz(uint32_t value) {
+int __inline __builtin_clz(uint32_t value) {
   unsigned long leading_zero = 0;
   return _BitScanReverse(&leading_zero, value) == 0 ? 0 : (31 - leading_zero);
 }
 
-uint32_t __inline __builtin_ctz(uint32_t value) {
+int __inline __builtin_ctz(uint32_t value) {
   unsigned long trailing_zero = 0;
   return _BitScanForward(&trailing_zero, value) == 0 ? 32 : trailing_zero;
 }
 
-uint32_t __inline __builtin_ctzl(uint64_t value) {
+// NOTE: avoid ctzl / clzl since long is 32 bits for MSVC
+
+int __inline __builtin_ctzll(uint64_t value) {
 #ifdef _M_X64
   unsigned long trailing_zero = 0;
   return _BitScanForward64(&trailing_zero, value) == 0 ? 64 : trailing_zero;

include/synthetic.h

@@ -218,7 +218,7 @@ class ZipfianGenerator {
 
   double zeta(int nn, double ttheta) {
     double sum = 0;
-    for (long i = 0; i < nn; i++) {
+    for (int i = 0; i < nn; i++) {
       sum += 1 / (pow(i + 1, ttheta));
     }
     return sum;

makefile.vc

@@ -18,11 +18,11 @@ LINK=link.exe
 INC = /Iinclude
 
 !IF "$(DEBUG)"=="yes"
-CFLAGS = /nologo /MDd /LDd /Od /Zi /D_DEBUG /D__SSSE3__ /RTC1 /W3 /wd"4141" /GS /Gm /arch:AVX
+CFLAGS = /nologo /MDd /LDd /Od /Zi /D_DEBUG /D__SSSE3__ /RTC1 /W3 /wd"4141" /GS /Gm /arch:AVX /EHsc
 ARFLAGS = /nologo
 LDFLAGS = /nologo /debug /nodefaultlib:msvcrt
 !ELSE
-CFLAGS = /nologo /MD /O2 /Zi /DNDEBUG /D__SSSE3__ /W3 /wd"4141" /Gm- /GS /Gy /Oi /GL /MP /arch:AVX
+CFLAGS = /nologo /MD /O2 /Zi /DNDEBUG /D__SSSE3__ /W3 /wd"4141" /Gm- /GS /Gy /Oi /GL /MP /arch:AVX /EHsc
 ARFLAGS = /nologo /LTCG
 LDFLAGS = /nologo /LTCG /DYNAMICBASE /incremental:no /debug /opt:ref,icf
 !ENDIF
@@ -42,6 +42,10 @@ unit: lib
 	$(CC) $(INC) $(CFLAGS) /c src/unit.cpp
 	$(LINK) $(LDFLAGS) /OUT:unit.exe unit.obj simdcomp_a.lib
 
+example: lib
+	$(CC) $(INC) $(CFLAGS) /c example.cpp
+	$(LINK) $(LDFLAGS) /OUT:example.exe example.obj simdcomp_a.lib
+
 clean:
 	del /Q *.obj
 	del /Q *.lib