c2_intelJccErratum_x86.hpp

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#ifndef CPU_X86_INTELJCCERRATUM_X86_HPP
#define CPU_X86_INTELJCCERRATUM_X86_HPP

#include "memory/allocation.hpp"
#include "utilities/globalDefinitions.hpp"

class Block;
class Compile;
class MachNode;
class MacroAssembler;
class PhaseCFG;
class PhaseRegAlloc;

class IntelJccErratum : public AllStatic {
private:
  // Compute which 32 byte boundary an address corresponds to
  static uintptr_t boundary(uintptr_t addr);
  static int jcc_erratum_taint_node(MachNode* node, PhaseRegAlloc* regalloc);

public:
  static bool is_crossing_or_ending_at_32_byte_boundary(uintptr_t start_pc, uintptr_t end_pc);
  static bool is_jcc_erratum_branch(const MachNode* node);
  // Analyze JCC erratum branches. Affected nodes get tagged with Flag_intel_jcc_erratum.
  // The function returns a conservative estimate of all required nops on all mach nodes.
  static int tag_affected_machnodes(Compile* C, PhaseCFG* cfg, PhaseRegAlloc* regalloc);
  // Computes the exact padding for a mach node
  static int compute_padding(uintptr_t current_offset, const MachNode* mach, Block* block, uint index_in_block, PhaseRegAlloc* regalloc);
  static int largest_jcc_size() { return 20; }
};

class IntelJccErratumAlignment {
private:
  MacroAssembler& _masm;
  uintptr_t       _start_pc;

  uintptr_t pc();

public:
  IntelJccErratumAlignment(MacroAssembler& masm, int jcc_size);
  ~IntelJccErratumAlignment();
};

#endif // CPU_X86_INTELJCCERRATUM_X86_HPP