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microregop.cc
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1 /*
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37 
38 #include "arch/x86/insts/microregop.hh"
39 
40 #include <string>
41 
42 #include "arch/x86/regs/misc.hh"
43 #include "base/condcodes.hh"
44 #include "debug/X86.hh"
45 
46 namespace gem5
47 {
48 
49 namespace X86ISA
50 {
51 
52 uint64_t
53 RegOpBase::genFlags(uint64_t old_flags, uint64_t flag_mask,
54  uint64_t _dest, uint64_t _src1, uint64_t _src2, bool subtract) const
55 {
56  DPRINTF(X86, "flag_mask = %#x\n", flag_mask);
57  uint64_t flags = old_flags & ~flag_mask;
58  if (flag_mask & (ECFBit | CFBit)) {
59  if (findCarry(dataSize*8, _dest, _src1, _src2))
60  flags |= (flag_mask & (ECFBit | CFBit));
61  if (subtract)
62  flags ^= (flag_mask & (ECFBit | CFBit));
63  }
64  if (flag_mask & PFBit && !findParity(8, _dest))
65  flags |= PFBit;
66  if (flag_mask & AFBit) {
67  if (findCarry(4, _dest, _src1, _src2))
68  flags |= AFBit;
69  if (subtract)
70  flags ^= AFBit;
71  }
72  if (flag_mask & (EZFBit | ZFBit) && findZero(dataSize * 8, _dest))
73  flags |= (flag_mask & (EZFBit | ZFBit));
74  if (flag_mask & SFBit && findNegative(dataSize * 8, _dest))
75  flags |= SFBit;
76  if (flag_mask & OFBit && findOverflow(dataSize * 8, _dest, _src1, _src2))
77  flags |= OFBit;
78  return flags;
79 }
80 
81 } // namespace X86ISA
82 } // namespace gem5
gem5::X86ISA::SFBit
@ SFBit
Definition: misc.hh:65
gem5::X86ISA::RegOpBase::dataSize
const uint8_t dataSize
Definition: microregop.hh:69
microregop.hh
gem5::X86ISA::ZFBit
@ ZFBit
Definition: misc.hh:64
gem5::findOverflow
static bool findOverflow(int width, uint64_t dest, uint64_t src1, uint64_t src2)
Calculate the overflow flag from an addition.
Definition: condcodes.hh:98
gem5::findZero
static bool findZero(int width, uint64_t dest)
Calculate the zero flag.
Definition: condcodes.hh:152
gem5::X86ISA::CFBit
@ CFBit
Definition: misc.hh:59
DPRINTF
#define DPRINTF(x,...)
Definition: trace.hh:186
gem5::X86ISA::EZFBit
@ EZFBit
Definition: misc.hh:63
gem5::StaticInst::flags
std::bitset< Num_Flags > flags
Flag values for this instruction.
Definition: static_inst.hh:103
gem5::findCarry
static bool findCarry(int width, uint64_t dest, uint64_t src1, uint64_t src2)
Calculate the carry flag from an addition.
Definition: condcodes.hh:84
gem5::X86ISA::ECFBit
@ ECFBit
Definition: misc.hh:61
gem5::findParity
static bool findParity(int width, uint64_t dest)
Calculate the parity of a value.
Definition: condcodes.hh:123
gem5::X86ISA::OFBit
@ OFBit
Definition: misc.hh:67
gem5::findNegative
static bool findNegative(int width, uint64_t dest)
Calculate the negative flag.
Definition: condcodes.hh:141
condcodes.hh
gem5::X86ISA::AFBit
@ AFBit
Definition: misc.hh:62
gem5::X86ISA::PFBit
@ PFBit
Definition: misc.hh:60
gem5::X86ISA::RegOpBase::genFlags
uint64_t genFlags(uint64_t old_flags, uint64_t flag_mask, uint64_t _dest, uint64_t _src1, uint64_t _src2, bool subtract=false) const
Definition: microregop.cc:53
gem5
Reference material can be found at the JEDEC website: UFS standard http://www.jedec....
Definition: decoder.cc:40
misc.hh
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