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Diffstat (limited to 'disas/libvixl/utils.cc')
-rw-r--r--disas/libvixl/utils.cc37
1 files changed, 19 insertions, 18 deletions
diff --git a/disas/libvixl/utils.cc b/disas/libvixl/utils.cc
index a45fb95f47..c9c05d1e18 100644
--- a/disas/libvixl/utils.cc
+++ b/disas/libvixl/utils.cc
@@ -58,9 +58,9 @@ double rawbits_to_double(uint64_t bits) {
int CountLeadingZeros(uint64_t value, int width) {
- ASSERT((width == 32) || (width == 64));
+ VIXL_ASSERT((width == 32) || (width == 64));
int count = 0;
- uint64_t bit_test = 1UL << (width - 1);
+ uint64_t bit_test = UINT64_C(1) << (width - 1);
while ((count < width) && ((bit_test & value) == 0)) {
count++;
bit_test >>= 1;
@@ -70,7 +70,7 @@ int CountLeadingZeros(uint64_t value, int width) {
int CountLeadingSignBits(int64_t value, int width) {
- ASSERT((width == 32) || (width == 64));
+ VIXL_ASSERT((width == 32) || (width == 64));
if (value >= 0) {
return CountLeadingZeros(value, width) - 1;
} else {
@@ -80,7 +80,7 @@ int CountLeadingSignBits(int64_t value, int width) {
int CountTrailingZeros(uint64_t value, int width) {
- ASSERT((width == 32) || (width == 64));
+ VIXL_ASSERT((width == 32) || (width == 64));
int count = 0;
while ((count < width) && (((value >> count) & 1) == 0)) {
count++;
@@ -92,10 +92,10 @@ int CountTrailingZeros(uint64_t value, int width) {
int CountSetBits(uint64_t value, int width) {
// TODO: Other widths could be added here, as the implementation already
// supports them.
- ASSERT((width == 32) || (width == 64));
+ VIXL_ASSERT((width == 32) || (width == 64));
// Mask out unused bits to ensure that they are not counted.
- value &= (0xffffffffffffffffULL >> (64-width));
+ value &= (UINT64_C(0xffffffffffffffff) >> (64-width));
// Add up the set bits.
// The algorithm works by adding pairs of bit fields together iteratively,
@@ -108,18 +108,19 @@ int CountSetBits(uint64_t value, int width) {
// value = h+g+f+e d+c+b+a
// \ |
// value = h+g+f+e+d+c+b+a
- value = ((value >> 1) & 0x5555555555555555ULL) +
- (value & 0x5555555555555555ULL);
- value = ((value >> 2) & 0x3333333333333333ULL) +
- (value & 0x3333333333333333ULL);
- value = ((value >> 4) & 0x0f0f0f0f0f0f0f0fULL) +
- (value & 0x0f0f0f0f0f0f0f0fULL);
- value = ((value >> 8) & 0x00ff00ff00ff00ffULL) +
- (value & 0x00ff00ff00ff00ffULL);
- value = ((value >> 16) & 0x0000ffff0000ffffULL) +
- (value & 0x0000ffff0000ffffULL);
- value = ((value >> 32) & 0x00000000ffffffffULL) +
- (value & 0x00000000ffffffffULL);
+ const uint64_t kMasks[] = {
+ UINT64_C(0x5555555555555555),
+ UINT64_C(0x3333333333333333),
+ UINT64_C(0x0f0f0f0f0f0f0f0f),
+ UINT64_C(0x00ff00ff00ff00ff),
+ UINT64_C(0x0000ffff0000ffff),
+ UINT64_C(0x00000000ffffffff),
+ };
+
+ for (unsigned i = 0; i < (sizeof(kMasks) / sizeof(kMasks[0])); i++) {
+ int shift = 1 << i;
+ value = ((value >> shift) & kMasks[i]) + (value & kMasks[i]);
+ }
return value;
}