WasmMemoryInformation.cpp [plain text]
#include "config.h"
#include "WasmMemoryInformation.h"
#if ENABLE(WEBASSEMBLY)
#include "WasmCallingConvention.h"
#include "WasmContext.h"
#include "WasmMemory.h"
#include <wtf/NeverDestroyed.h>
namespace JSC { namespace Wasm {
static Vector<GPRReg> getPinnedRegisters(unsigned remainingPinnedRegisters)
{
Vector<GPRReg> registers;
jscCallingConvention().m_calleeSaveRegisters.forEach([&] (Reg reg) {
if (!reg.isGPR())
return;
GPRReg gpr = reg.gpr();
if (!remainingPinnedRegisters || RegisterSet::stackRegisters().get(reg))
return;
--remainingPinnedRegisters;
registers.append(gpr);
});
return registers;
}
const PinnedRegisterInfo& PinnedRegisterInfo::get()
{
static LazyNeverDestroyed<PinnedRegisterInfo> staticPinnedRegisterInfo;
static std::once_flag staticPinnedRegisterInfoFlag;
std::call_once(staticPinnedRegisterInfoFlag, [] () {
Vector<PinnedSizeRegisterInfo> sizeRegisters;
GPRReg baseMemoryPointer = InvalidGPRReg;
GPRReg wasmContextPointer = InvalidGPRReg;
Vector<unsigned> pinnedSizes = { 0 };
unsigned numberOfPinnedRegisters = pinnedSizes.size() + 1;
if (!useFastTLSForContext())
++numberOfPinnedRegisters;
Vector<GPRReg> pinnedRegs = getPinnedRegisters(numberOfPinnedRegisters);
baseMemoryPointer = pinnedRegs.takeLast();
if (!useFastTLSForContext())
wasmContextPointer = pinnedRegs.takeLast();
ASSERT(pinnedSizes.size() == pinnedRegs.size());
for (unsigned i = 0; i < pinnedSizes.size(); ++i)
sizeRegisters.append({ pinnedRegs[i], pinnedSizes[i] });
staticPinnedRegisterInfo.construct(WTFMove(sizeRegisters), baseMemoryPointer, wasmContextPointer);
});
return staticPinnedRegisterInfo.get();
}
PinnedRegisterInfo::PinnedRegisterInfo(Vector<PinnedSizeRegisterInfo>&& sizeRegisters, GPRReg baseMemoryPointer, GPRReg wasmContextPointer)
: sizeRegisters(WTFMove(sizeRegisters))
, baseMemoryPointer(baseMemoryPointer)
, wasmContextPointer(wasmContextPointer)
{
}
MemoryInformation::MemoryInformation(PageCount initial, PageCount maximum, bool isImport)
: m_initial(initial)
, m_maximum(maximum)
, m_isImport(isImport)
{
RELEASE_ASSERT(!!m_initial);
RELEASE_ASSERT(!m_maximum || m_maximum >= m_initial);
ASSERT(!!*this);
}
} }
#endif // ENABLE(WEBASSEMBLY)