Export of internal Abseil changes
-- d35c72d705155dcd89a92835103540f14c643d10 by Gennadiy Rozental <rogeeff@google.com>: helpxml changed to report types of flags with built-in value type. PiperOrigin-RevId: 275131440 -- f3478792943d7dd40a6ef6083a8e5d374f43a65e by Abseil Team <absl-team@google.com>: Add space padding tests for hex conversions. PiperOrigin-RevId: 275120155 -- 7c2e4725403e173660f33f94af686a75d3722936 by Andy Soffer <asoffer@google.com>: Fix https://github.com/abseil/abseil-cpp/issues/379 by renaming `roundup` to `round_up` PiperOrigin-RevId: 275106110 -- 84cb30d6ee509961ac4359cfdda1360973b9527d by Laramie Leavitt <lar@google.com>: Move random_internal::wide_multiply into a file by the same name. PiperOrigin-RevId: 275059359 -- 06d691a8c187b5d899e7863784b23bdcfd580cb2 by Abseil Team <absl-team@google.com>: Add missing "return" keyword. PiperOrigin-RevId: 275036408 GitOrigin-RevId: d35c72d705155dcd89a92835103540f14c643d10 Change-Id: Id837b4de6c9cfe18f0a088363754bfe389df985b
This commit is contained in:
parent
ab3552a189
commit
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12 changed files with 275 additions and 118 deletions
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@ -211,7 +211,7 @@ struct LowLevelAlloc::Arena {
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// Result of sysconf(_SC_PAGESIZE)
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// Result of sysconf(_SC_PAGESIZE)
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const size_t pagesize;
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const size_t pagesize;
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// Lowest power of two >= max(16, sizeof(AllocList))
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// Lowest power of two >= max(16, sizeof(AllocList))
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const size_t roundup;
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const size_t round_up;
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// Smallest allocation block size
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// Smallest allocation block size
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const size_t min_size;
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const size_t min_size;
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// PRNG state
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// PRNG state
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@ -336,11 +336,11 @@ size_t GetPageSize() {
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size_t RoundedUpBlockSize() {
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size_t RoundedUpBlockSize() {
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// Round up block sizes to a power of two close to the header size.
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// Round up block sizes to a power of two close to the header size.
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size_t roundup = 16;
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size_t round_up = 16;
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while (roundup < sizeof(AllocList::Header)) {
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while (round_up < sizeof(AllocList::Header)) {
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roundup += roundup;
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round_up += round_up;
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}
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}
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return roundup;
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return round_up;
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}
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}
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} // namespace
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} // namespace
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@ -350,8 +350,8 @@ LowLevelAlloc::Arena::Arena(uint32_t flags_value)
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allocation_count(0),
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allocation_count(0),
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flags(flags_value),
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flags(flags_value),
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pagesize(GetPageSize()),
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pagesize(GetPageSize()),
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roundup(RoundedUpBlockSize()),
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round_up(RoundedUpBlockSize()),
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min_size(2 * roundup),
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min_size(2 * round_up),
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random(0) {
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random(0) {
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freelist.header.size = 0;
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freelist.header.size = 0;
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freelist.header.magic =
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freelist.header.magic =
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@ -528,7 +528,7 @@ static void *DoAllocWithArena(size_t request, LowLevelAlloc::Arena *arena) {
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ArenaLock section(arena);
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ArenaLock section(arena);
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// round up with header
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// round up with header
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size_t req_rnd = RoundUp(CheckedAdd(request, sizeof (s->header)),
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size_t req_rnd = RoundUp(CheckedAdd(request, sizeof (s->header)),
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arena->roundup);
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arena->round_up);
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for (;;) { // loop until we find a suitable region
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for (;;) { // loop until we find a suitable region
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// find the minimum levels that a block of this size must have
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// find the minimum levels that a block of this size must have
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int i = LLA_SkiplistLevels(req_rnd, arena->min_size, nullptr) - 1;
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int i = LLA_SkiplistLevels(req_rnd, arena->min_size, nullptr) - 1;
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@ -121,7 +121,7 @@ class Flag {
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bool IsModified() const { return GetImpl()->IsModified(); }
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bool IsModified() const { return GetImpl()->IsModified(); }
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void SetModified(bool is_modified) { GetImpl()->SetModified(is_modified); }
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void SetModified(bool is_modified) { GetImpl()->SetModified(is_modified); }
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bool IsSpecifiedOnCommandLine() const {
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bool IsSpecifiedOnCommandLine() const {
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GetImpl()->IsSpecifiedOnCommandLine();
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return GetImpl()->IsSpecifiedOnCommandLine();
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}
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}
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absl::string_view Typename() const { return GetImpl()->Typename(); }
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absl::string_view Typename() const { return GetImpl()->Typename(); }
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std::string Filename() const { return GetImpl()->Filename(); }
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std::string Filename() const { return GetImpl()->Filename(); }
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@ -47,6 +47,27 @@ namespace absl {
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namespace flags_internal {
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namespace flags_internal {
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namespace {
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namespace {
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absl::string_view TypenameForHelp(const flags_internal::CommandLineFlag& flag) {
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// Only report names of v1 built-in types
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#define HANDLE_V1_BUILTIN_TYPE(t) \
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if (flag.IsOfType<t>()) { \
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return #t; \
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}
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HANDLE_V1_BUILTIN_TYPE(bool);
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HANDLE_V1_BUILTIN_TYPE(int32_t);
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HANDLE_V1_BUILTIN_TYPE(int64_t);
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HANDLE_V1_BUILTIN_TYPE(uint64_t);
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HANDLE_V1_BUILTIN_TYPE(double);
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#undef HANDLE_V1_BUILTIN_TYPE
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if (flag.IsOfType<std::string>()) {
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return "string";
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}
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return "";
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}
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// This class is used to emit an XML element with `tag` and `text`.
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// This class is used to emit an XML element with `tag` and `text`.
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// It adds opening and closing tags and escapes special characters in the text.
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// It adds opening and closing tags and escapes special characters in the text.
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// For example:
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// For example:
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@ -186,7 +207,7 @@ void FlagHelpHumanReadable(const flags_internal::CommandLineFlag& flag,
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// Flag data type (for V1 flags only).
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// Flag data type (for V1 flags only).
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if (!flag.IsAbseilFlag() && !flag.IsRetired()) {
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if (!flag.IsAbseilFlag() && !flag.IsRetired()) {
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printer.Write(absl::StrCat("type: ", flag.Typename(), ";"));
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printer.Write(absl::StrCat("type: ", TypenameForHelp(flag), ";"));
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}
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}
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// The listed default value will be the actual default from the flag
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// The listed default value will be the actual default from the flag
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@ -223,6 +244,9 @@ void FlagsHelpImpl(std::ostream& out, flags_internal::FlagKindFilter filter_cb,
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} else {
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} else {
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// XML schema is not a part of our public API for now.
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// XML schema is not a part of our public API for now.
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out << "<?xml version=\"1.0\"?>\n"
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out << "<?xml version=\"1.0\"?>\n"
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<< "<!-- This output should be used with care. We do not report type "
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"names for flags with user defined types -->\n"
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<< "<!-- Prefer flag only_check_args for validating flag inputs -->\n"
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// The document.
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// The document.
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<< "<AllFlags>\n"
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<< "<AllFlags>\n"
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// The program name and usage.
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// The program name and usage.
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@ -76,6 +76,7 @@ cc_library(
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"//absl/random/internal:iostream_state_saver",
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"//absl/random/internal:iostream_state_saver",
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"//absl/random/internal:traits",
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"//absl/random/internal:traits",
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"//absl/random/internal:uniform_helper",
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"//absl/random/internal:uniform_helper",
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"//absl/random/internal:wide_multiply",
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"//absl/strings",
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"//absl/strings",
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"//absl/types:span",
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"//absl/types:span",
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],
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],
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@ -65,6 +65,7 @@ absl_cc_library(
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absl::random_internal_iostream_state_saver
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absl::random_internal_iostream_state_saver
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absl::random_internal_traits
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absl::random_internal_traits
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absl::random_internal_uniform_helper
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absl::random_internal_uniform_helper
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absl::random_internal_wide_multiply
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absl::strings
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absl::strings
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absl::span
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absl::span
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absl::type_traits
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absl::type_traits
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@ -557,6 +558,22 @@ absl_cc_library(
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absl::random_internal_traits
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absl::random_internal_traits
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)
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)
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# Internal-only target, do not depend on directly.
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absl_cc_library(
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NAME
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random_internal_wide_multiply
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HDRS
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"internal/wide_multiply.h"
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COPTS
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${ABSL_DEFAULT_COPTS}
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LINKOPTS
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${ABSL_DEFAULT_LINKOPTS}
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DEPS
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absl::bits
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absl::config
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absl::int128
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)
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# Internal-only target, do not depend on directly.
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# Internal-only target, do not depend on directly.
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absl_cc_library(
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absl_cc_library(
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NAME
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NAME
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@ -1033,3 +1050,20 @@ absl_cc_test(
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absl::random_internal_iostream_state_saver
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absl::random_internal_iostream_state_saver
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gtest_main
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gtest_main
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)
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)
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# Internal-only target, do not depend on directly.
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absl_cc_test(
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NAME
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random_internal_wide_multiply_test
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SRCS
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internal/wide_multiply_test.cc
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COPTS
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${ABSL_TEST_COPTS}
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LINKOPTS
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${ABSL_DEFAULT_LINKOPTS}
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DEPS
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absl::random_internal_wide_multiply
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absl::bits
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absl::int128
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gtest_main
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)
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@ -200,6 +200,19 @@ cc_library(
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deps = ["//absl/base:bits"],
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deps = ["//absl/base:bits"],
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)
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)
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cc_library(
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name = "wide_multiply",
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hdrs = ["wide_multiply.h"],
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copts = ABSL_DEFAULT_COPTS,
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linkopts = ABSL_DEFAULT_LINKOPTS,
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deps = [
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":traits",
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"//absl/base:bits",
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"//absl/base:config",
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"//absl/numeric:int128",
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],
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)
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cc_library(
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cc_library(
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name = "nonsecure_base",
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name = "nonsecure_base",
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hdrs = ["nonsecure_base.h"],
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hdrs = ["nonsecure_base.h"],
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@ -598,6 +611,20 @@ cc_test(
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],
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],
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)
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)
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cc_test(
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name = "wide_multiply_test",
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size = "small",
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srcs = ["wide_multiply_test.cc"],
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copts = ABSL_TEST_COPTS,
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linkopts = ABSL_DEFAULT_LINKOPTS,
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deps = [
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":wide_multiply",
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"//absl/base:bits",
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"//absl/numeric:int128",
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"@com_google_googletest//:gtest_main",
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],
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)
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cc_library(
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cc_library(
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name = "nanobenchmark",
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name = "nanobenchmark",
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srcs = ["nanobenchmark.cc"],
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srcs = ["nanobenchmark.cc"],
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@ -188,72 +188,6 @@ struct RandU64ToReal<float> {
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}
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}
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};
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};
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inline uint128 MultiplyU64ToU128(uint64_t a, uint64_t b) {
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#if defined(ABSL_HAVE_INTRINSIC_INT128)
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return uint128(static_cast<__uint128_t>(a) * b);
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#elif defined(ABSL_INTERNAL_USE_UMUL128)
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// uint64_t * uint64_t => uint128 multiply using imul intrinsic on MSVC.
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uint64_t high = 0;
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const uint64_t low = _umul128(a, b, &high);
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return absl::MakeUint128(high, low);
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#else
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// uint128(a) * uint128(b) in emulated mode computes a full 128-bit x 128-bit
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// multiply. However there are many cases where that is not necessary, and it
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// is only necessary to support a 64-bit x 64-bit = 128-bit multiply. This is
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// for those cases.
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const uint64_t a00 = static_cast<uint32_t>(a);
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const uint64_t a32 = a >> 32;
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const uint64_t b00 = static_cast<uint32_t>(b);
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const uint64_t b32 = b >> 32;
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const uint64_t c00 = a00 * b00;
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const uint64_t c32a = a00 * b32;
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const uint64_t c32b = a32 * b00;
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const uint64_t c64 = a32 * b32;
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const uint32_t carry =
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static_cast<uint32_t>(((c00 >> 32) + static_cast<uint32_t>(c32a) +
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static_cast<uint32_t>(c32b)) >>
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32);
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return absl::MakeUint128(c64 + (c32a >> 32) + (c32b >> 32) + carry,
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c00 + (c32a << 32) + (c32b << 32));
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#endif
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}
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// wide_multiply<T> multiplies two N-bit values to a 2N-bit result.
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template <typename UIntType>
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struct wide_multiply {
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static constexpr size_t kN = std::numeric_limits<UIntType>::digits;
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using input_type = UIntType;
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using result_type = typename random_internal::unsigned_bits<kN * 2>::type;
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static result_type multiply(input_type a, input_type b) {
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return static_cast<result_type>(a) * b;
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}
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static input_type hi(result_type r) { return r >> kN; }
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static input_type lo(result_type r) { return r; }
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static_assert(std::is_unsigned<UIntType>::value,
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"Class-template wide_multiply<> argument must be unsigned.");
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};
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#ifndef ABSL_HAVE_INTRINSIC_INT128
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template <>
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struct wide_multiply<uint64_t> {
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using input_type = uint64_t;
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using result_type = uint128;
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static result_type multiply(uint64_t a, uint64_t b) {
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return MultiplyU64ToU128(a, b);
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}
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static uint64_t hi(result_type r) { return Uint128High64(r); }
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static uint64_t lo(result_type r) { return Uint128Low64(r); }
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};
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#endif
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} // namespace random_internal
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} // namespace random_internal
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} // namespace absl
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} // namespace absl
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@ -461,46 +461,4 @@ TEST(DistributionImplTest, ExhaustiveFloat) {
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}
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}
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}
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}
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TEST(DistributionImplTest, MultiplyU64ToU128Test) {
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using absl::random_internal::MultiplyU64ToU128;
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constexpr uint64_t k1 = 1;
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constexpr uint64_t kMax = ~static_cast<uint64_t>(0);
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EXPECT_EQ(absl::uint128(0), MultiplyU64ToU128(0, 0));
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// Max uint64
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EXPECT_EQ(MultiplyU64ToU128(kMax, kMax),
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absl::MakeUint128(0xfffffffffffffffe, 0x0000000000000001));
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EXPECT_EQ(absl::MakeUint128(0, kMax), MultiplyU64ToU128(kMax, 1));
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EXPECT_EQ(absl::MakeUint128(0, kMax), MultiplyU64ToU128(1, kMax));
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for (int i = 0; i < 64; ++i) {
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EXPECT_EQ(absl::MakeUint128(0, kMax) << i,
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MultiplyU64ToU128(kMax, k1 << i));
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EXPECT_EQ(absl::MakeUint128(0, kMax) << i,
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MultiplyU64ToU128(k1 << i, kMax));
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}
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// 1-bit x 1-bit.
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for (int i = 0; i < 64; ++i) {
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for (int j = 0; j < 64; ++j) {
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EXPECT_EQ(absl::MakeUint128(0, 1) << (i + j),
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MultiplyU64ToU128(k1 << i, k1 << j));
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EXPECT_EQ(absl::MakeUint128(0, 1) << (i + j),
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MultiplyU64ToU128(k1 << i, k1 << j));
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}
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}
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// Verified multiplies
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EXPECT_EQ(MultiplyU64ToU128(0xffffeeeeddddcccc, 0xbbbbaaaa99998888),
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absl::MakeUint128(0xbbbb9e2692c5dddc, 0xc28f7531048d2c60));
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|
||||||
EXPECT_EQ(MultiplyU64ToU128(0x0123456789abcdef, 0xfedcba9876543210),
|
|
||||||
absl::MakeUint128(0x0121fa00ad77d742, 0x2236d88fe5618cf0));
|
|
||||||
EXPECT_EQ(MultiplyU64ToU128(0x0123456789abcdef, 0xfdb97531eca86420),
|
|
||||||
absl::MakeUint128(0x0120ae99d26725fc, 0xce197f0ecac319e0));
|
|
||||||
EXPECT_EQ(MultiplyU64ToU128(0x97a87f4f261ba3f2, 0xfedcba9876543210),
|
|
||||||
absl::MakeUint128(0x96fbf1a8ae78d0ba, 0x5a6dd4b71f278320));
|
|
||||||
EXPECT_EQ(MultiplyU64ToU128(0xfedcba9876543210, 0xfdb97531eca86420),
|
|
||||||
absl::MakeUint128(0xfc98c6981a413e22, 0x342d0bbf48948200));
|
|
||||||
}
|
|
||||||
|
|
||||||
} // namespace
|
} // namespace
|
||||||
|
|
109
absl/random/internal/wide_multiply.h
Normal file
109
absl/random/internal/wide_multiply.h
Normal file
|
@ -0,0 +1,109 @@
|
||||||
|
// Copyright 2017 The Abseil Authors.
|
||||||
|
//
|
||||||
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
||||||
|
// you may not use this file except in compliance with the License.
|
||||||
|
// You may obtain a copy of the License at
|
||||||
|
//
|
||||||
|
// https://www.apache.org/licenses/LICENSE-2.0
|
||||||
|
//
|
||||||
|
// Unless required by applicable law or agreed to in writing, software
|
||||||
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
||||||
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||||
|
// See the License for the specific language governing permissions and
|
||||||
|
// limitations under the License.
|
||||||
|
|
||||||
|
#ifndef ABSL_RANDOM_INTERNAL_WIDE_MULTIPLY_H_
|
||||||
|
#define ABSL_RANDOM_INTERNAL_WIDE_MULTIPLY_H_
|
||||||
|
|
||||||
|
#include <cstdint>
|
||||||
|
#include <limits>
|
||||||
|
#include <type_traits>
|
||||||
|
|
||||||
|
#if (defined(_WIN32) || defined(_WIN64)) && defined(_M_IA64)
|
||||||
|
#include <intrin.h> // NOLINT(build/include_order)
|
||||||
|
#pragma intrinsic(_umul128)
|
||||||
|
#define ABSL_INTERNAL_USE_UMUL128 1
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#include "absl/base/config.h"
|
||||||
|
#include "absl/base/internal/bits.h"
|
||||||
|
#include "absl/numeric/int128.h"
|
||||||
|
#include "absl/random/internal/traits.h"
|
||||||
|
|
||||||
|
namespace absl {
|
||||||
|
namespace random_internal {
|
||||||
|
|
||||||
|
// Helper object to multiply two 64-bit values to a 128-bit value.
|
||||||
|
// MultiplyU64ToU128 multiplies two 64-bit values to a 128-bit value.
|
||||||
|
// If an intrinsic is available, it is used, otherwise use native 32-bit
|
||||||
|
// multiplies to construct the result.
|
||||||
|
inline uint128 MultiplyU64ToU128(uint64_t a, uint64_t b) {
|
||||||
|
#if defined(ABSL_HAVE_INTRINSIC_INT128)
|
||||||
|
return uint128(static_cast<__uint128_t>(a) * b);
|
||||||
|
#elif defined(ABSL_INTERNAL_USE_UMUL128)
|
||||||
|
// uint64_t * uint64_t => uint128 multiply using imul intrinsic on MSVC.
|
||||||
|
uint64_t high = 0;
|
||||||
|
const uint64_t low = _umul128(a, b, &high);
|
||||||
|
return absl::MakeUint128(high, low);
|
||||||
|
#else
|
||||||
|
// uint128(a) * uint128(b) in emulated mode computes a full 128-bit x 128-bit
|
||||||
|
// multiply. However there are many cases where that is not necessary, and it
|
||||||
|
// is only necessary to support a 64-bit x 64-bit = 128-bit multiply. This is
|
||||||
|
// for those cases.
|
||||||
|
const uint64_t a00 = static_cast<uint32_t>(a);
|
||||||
|
const uint64_t a32 = a >> 32;
|
||||||
|
const uint64_t b00 = static_cast<uint32_t>(b);
|
||||||
|
const uint64_t b32 = b >> 32;
|
||||||
|
|
||||||
|
const uint64_t c00 = a00 * b00;
|
||||||
|
const uint64_t c32a = a00 * b32;
|
||||||
|
const uint64_t c32b = a32 * b00;
|
||||||
|
const uint64_t c64 = a32 * b32;
|
||||||
|
|
||||||
|
const uint32_t carry =
|
||||||
|
static_cast<uint32_t>(((c00 >> 32) + static_cast<uint32_t>(c32a) +
|
||||||
|
static_cast<uint32_t>(c32b)) >>
|
||||||
|
32);
|
||||||
|
|
||||||
|
return absl::MakeUint128(c64 + (c32a >> 32) + (c32b >> 32) + carry,
|
||||||
|
c00 + (c32a << 32) + (c32b << 32));
|
||||||
|
#endif
|
||||||
|
}
|
||||||
|
|
||||||
|
// wide_multiply<T> multiplies two N-bit values to a 2N-bit result.
|
||||||
|
template <typename UIntType>
|
||||||
|
struct wide_multiply {
|
||||||
|
static constexpr size_t kN = std::numeric_limits<UIntType>::digits;
|
||||||
|
using input_type = UIntType;
|
||||||
|
using result_type = typename random_internal::unsigned_bits<kN * 2>::type;
|
||||||
|
|
||||||
|
static result_type multiply(input_type a, input_type b) {
|
||||||
|
return static_cast<result_type>(a) * b;
|
||||||
|
}
|
||||||
|
|
||||||
|
static input_type hi(result_type r) { return r >> kN; }
|
||||||
|
static input_type lo(result_type r) { return r; }
|
||||||
|
|
||||||
|
static_assert(std::is_unsigned<UIntType>::value,
|
||||||
|
"Class-template wide_multiply<> argument must be unsigned.");
|
||||||
|
};
|
||||||
|
|
||||||
|
#ifndef ABSL_HAVE_INTRINSIC_INT128
|
||||||
|
template <>
|
||||||
|
struct wide_multiply<uint64_t> {
|
||||||
|
using input_type = uint64_t;
|
||||||
|
using result_type = uint128;
|
||||||
|
|
||||||
|
static result_type multiply(uint64_t a, uint64_t b) {
|
||||||
|
return MultiplyU64ToU128(a, b);
|
||||||
|
}
|
||||||
|
|
||||||
|
static uint64_t hi(result_type r) { return Uint128High64(r); }
|
||||||
|
static uint64_t lo(result_type r) { return Uint128Low64(r); }
|
||||||
|
};
|
||||||
|
#endif
|
||||||
|
|
||||||
|
} // namespace random_internal
|
||||||
|
} // namespace absl
|
||||||
|
|
||||||
|
#endif // ABSL_RANDOM_INTERNAL_WIDE_MULTIPLY_H_
|
66
absl/random/internal/wide_multiply_test.cc
Normal file
66
absl/random/internal/wide_multiply_test.cc
Normal file
|
@ -0,0 +1,66 @@
|
||||||
|
// Copyright 2017 The Abseil Authors.
|
||||||
|
//
|
||||||
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
||||||
|
// you may not use this file except in compliance with the License.
|
||||||
|
// You may obtain a copy of the License at
|
||||||
|
//
|
||||||
|
// https://www.apache.org/licenses/LICENSE-2.0
|
||||||
|
//
|
||||||
|
// Unless required by applicable law or agreed to in writing, software
|
||||||
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
||||||
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||||
|
// See the License for the specific language governing permissions and
|
||||||
|
// limitations under the License.
|
||||||
|
|
||||||
|
#include "absl/random/internal/wide_multiply.h"
|
||||||
|
|
||||||
|
#include "gtest/gtest.h"
|
||||||
|
#include "absl/base/internal/bits.h"
|
||||||
|
#include "absl/numeric/int128.h"
|
||||||
|
|
||||||
|
using absl::random_internal::MultiplyU64ToU128;
|
||||||
|
|
||||||
|
namespace {
|
||||||
|
|
||||||
|
TEST(WideMultiplyTest, MultiplyU64ToU128Test) {
|
||||||
|
constexpr uint64_t k1 = 1;
|
||||||
|
constexpr uint64_t kMax = ~static_cast<uint64_t>(0);
|
||||||
|
|
||||||
|
EXPECT_EQ(absl::uint128(0), MultiplyU64ToU128(0, 0));
|
||||||
|
|
||||||
|
// Max uint64
|
||||||
|
EXPECT_EQ(MultiplyU64ToU128(kMax, kMax),
|
||||||
|
absl::MakeUint128(0xfffffffffffffffe, 0x0000000000000001));
|
||||||
|
EXPECT_EQ(absl::MakeUint128(0, kMax), MultiplyU64ToU128(kMax, 1));
|
||||||
|
EXPECT_EQ(absl::MakeUint128(0, kMax), MultiplyU64ToU128(1, kMax));
|
||||||
|
for (int i = 0; i < 64; ++i) {
|
||||||
|
EXPECT_EQ(absl::MakeUint128(0, kMax) << i,
|
||||||
|
MultiplyU64ToU128(kMax, k1 << i));
|
||||||
|
EXPECT_EQ(absl::MakeUint128(0, kMax) << i,
|
||||||
|
MultiplyU64ToU128(k1 << i, kMax));
|
||||||
|
}
|
||||||
|
|
||||||
|
// 1-bit x 1-bit.
|
||||||
|
for (int i = 0; i < 64; ++i) {
|
||||||
|
for (int j = 0; j < 64; ++j) {
|
||||||
|
EXPECT_EQ(absl::MakeUint128(0, 1) << (i + j),
|
||||||
|
MultiplyU64ToU128(k1 << i, k1 << j));
|
||||||
|
EXPECT_EQ(absl::MakeUint128(0, 1) << (i + j),
|
||||||
|
MultiplyU64ToU128(k1 << i, k1 << j));
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
// Verified multiplies
|
||||||
|
EXPECT_EQ(MultiplyU64ToU128(0xffffeeeeddddcccc, 0xbbbbaaaa99998888),
|
||||||
|
absl::MakeUint128(0xbbbb9e2692c5dddc, 0xc28f7531048d2c60));
|
||||||
|
EXPECT_EQ(MultiplyU64ToU128(0x0123456789abcdef, 0xfedcba9876543210),
|
||||||
|
absl::MakeUint128(0x0121fa00ad77d742, 0x2236d88fe5618cf0));
|
||||||
|
EXPECT_EQ(MultiplyU64ToU128(0x0123456789abcdef, 0xfdb97531eca86420),
|
||||||
|
absl::MakeUint128(0x0120ae99d26725fc, 0xce197f0ecac319e0));
|
||||||
|
EXPECT_EQ(MultiplyU64ToU128(0x97a87f4f261ba3f2, 0xfedcba9876543210),
|
||||||
|
absl::MakeUint128(0x96fbf1a8ae78d0ba, 0x5a6dd4b71f278320));
|
||||||
|
EXPECT_EQ(MultiplyU64ToU128(0xfedcba9876543210, 0xfdb97531eca86420),
|
||||||
|
absl::MakeUint128(0xfc98c6981a413e22, 0x342d0bbf48948200));
|
||||||
|
}
|
||||||
|
|
||||||
|
} // namespace
|
|
@ -38,6 +38,7 @@
|
||||||
#include "absl/random/internal/fast_uniform_bits.h"
|
#include "absl/random/internal/fast_uniform_bits.h"
|
||||||
#include "absl/random/internal/iostream_state_saver.h"
|
#include "absl/random/internal/iostream_state_saver.h"
|
||||||
#include "absl/random/internal/traits.h"
|
#include "absl/random/internal/traits.h"
|
||||||
|
#include "absl/random/internal/wide_multiply.h"
|
||||||
|
|
||||||
namespace absl {
|
namespace absl {
|
||||||
|
|
||||||
|
|
|
@ -204,6 +204,9 @@ void CheckHex64(uint64_t v) {
|
||||||
std::string actual = absl::StrCat(absl::Hex(v, absl::kZeroPad16));
|
std::string actual = absl::StrCat(absl::Hex(v, absl::kZeroPad16));
|
||||||
snprintf(expected, sizeof(expected), "%016" PRIx64, static_cast<uint64_t>(v));
|
snprintf(expected, sizeof(expected), "%016" PRIx64, static_cast<uint64_t>(v));
|
||||||
EXPECT_EQ(expected, actual) << " Input " << v;
|
EXPECT_EQ(expected, actual) << " Input " << v;
|
||||||
|
actual = absl::StrCat(absl::Hex(v, absl::kSpacePad16));
|
||||||
|
snprintf(expected, sizeof(expected), "%16" PRIx64, static_cast<uint64_t>(v));
|
||||||
|
EXPECT_EQ(expected, actual) << " Input " << v;
|
||||||
}
|
}
|
||||||
|
|
||||||
TEST(Numbers, TestFastPrints) {
|
TEST(Numbers, TestFastPrints) {
|
||||||
|
|
Loading…
Reference in a new issue