AirAllocateRegistersAndStackByLinearScan.h   [plain text]


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#pragma once

#if ENABLE(B3_JIT)

#include "CPU.h"
#include "Options.h"

namespace JSC { namespace B3 { namespace Air {

class Code;

// This implements the Poletto and Sarkar register allocator called "linear scan":
// http://dl.acm.org/citation.cfm?id=330250
//
// This is not Air's primary register allocator. We use it only when running at optLevel<2.
// That's not the default level. This register allocator is optimized primarily for running
// quickly. It's expected that improvements to this register allocator should focus on improving
// its execution time without much regard for the quality of generated code. If you want good
// code, use graph coloring.
//
// For Air's primary register allocator, see AirAllocateRegistersByGraphColoring.h|cpp.
//
// This also does stack allocation as an afterthought. It does not do any spill coalescing.
void allocateRegistersAndStackByLinearScan(Code&);

} } } // namespace JSC::B3::Air

#endif // ENABLE(B3_JIT)