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Simplify V8::FillHeapNumberWithRandom.

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Review URL: https://chromiumcodereview.appspot.com/9592047

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10975 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
yangguo@chromium.org 2012-03-09 09:51:34 +00:00
parent e6576f0938
commit 9f1846173c
1 changed files with 6 additions and 8 deletions
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14
src/v8.cc
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@ -223,19 +223,17 @@ typedef union {
Object* V8::FillHeapNumberWithRandom(Object* heap_number,
Context* context) {
double_int_union r;
uint64_t random_bits = Random(context);
// Make a double* from address (heap_number + sizeof(double)).
double_int_union* r = reinterpret_cast<double_int_union*>(
reinterpret_cast<char*>(heap_number) +
HeapNumber::kValueOffset - kHeapObjectTag);
// Convert 32 random bits to 0.(32 random bits) in a double
// by computing:
// ( 1.(20 0s)(32 random bits) x 2^20 ) - (1.0 x 2^20)).
const double binary_million = 1048576.0;
r->double_value = binary_million;
r->uint64_t_value |= random_bits;
r->double_value -= binary_million;
static const double binary_million = 1048576.0;
r.double_value = binary_million;
r.uint64_t_value |= random_bits;
r.double_value -= binary_million;
HeapNumber::cast(heap_number)->set_value(r.double_value);
return heap_number;
}