Module: Indis::ARM::PseudoCodeInstructionHelper

Included in:
InstructionHelper
Defined in:
lib/indis-arm/instruction_helper.rb

Instance Method Summary collapse

Instance Method Details

#ARMExpandImm(bits_imm12) ⇒ Object

A5.2.4



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# File 'lib/indis-arm/instruction_helper.rb', line 24

def ARMExpandImm(bits_imm12) # A5.2.4
  ARMExpandImm_C(bits_imm12, 0)[0] # FIXME APSR.C ???
end

#ARMExpandImm_C(bits_imm12, carry_in) ⇒ Object

A5.2.4



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# File 'lib/indis-arm/instruction_helper.rb', line 28

def ARMExpandImm_C(bits_imm12, carry_in) # A5.2.4
  unrotated_value = bits_imm12.bits(7, 0).zero_extend(32)
  Shift_C(unrotated_value, :SRType_ROR, 2*(bits_imm12.bits(11, 8).to_i), carry_in)
end

#DecodeImmShift(bits2_type, bits5_imm5) ⇒ Object 



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# File 'lib/indis-arm/instruction_helper.rb', line 33

def DecodeImmShift(bits2_type, bits5_imm5)
  imm = bits5_imm5.to_i
  case bits2_type.to_i
  when 0b00
    [:SRType_LSL, imm]
  when 0b01
    [:SRType_LSR, imm == 0 ? 32 : imm]
  when 0b10
    [:SRType_ASR, imm == 0 ? 32 : imm]
  when 0b11
    imm == 0 ? [:SRType_RRX, 1] : [:SRType_ROR, imm]
  end    
end

#LSL(bits_x, shift) ⇒ Object

A2.2.1

Raises:

  • (ArgumentError) 


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# File 'lib/indis-arm/instruction_helper.rb', line 90

def LSL(bits_x, shift) # A2.2.1
  raise ArgumentError unless shift >= 0
  bits_x << shift
end

#LSL_C(bits_x, shift) ⇒ Object

A2.2.1

Raises:

  • (ArgumentError) 


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# File 'lib/indis-arm/instruction_helper.rb', line 95

def LSL_C(bits_x, shift) # A2.2.1
  raise ArgumentError unless shift > 0
  [bits_x << shift, bits_x.bit(shift)]
end

#LSR(bits_x, shift) ⇒ Object

A2.2.1

Raises:

  • (ArgumentError) 


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# File 'lib/indis-arm/instruction_helper.rb', line 80

def LSR(bits_x, shift) # A2.2.1
  raise ArgumentError unless shift >= 0
  bits_x >> shift
end

#LSR_C(bits_x, shift) ⇒ Object

A2.2.1

Raises:

  • (ArgumentError) 


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# File 'lib/indis-arm/instruction_helper.rb', line 85

def LSR_C(bits_x, shift) # A2.2.1
  raise ArgumentError unless shift > 0
  [bits_x >> shift, bits_x.bit(shift-1)]
end

#ROR_C(bits_x, shift) ⇒ Object

A2.2.1

Raises:

  • (ArgumentError) 


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# File 'lib/indis-arm/instruction_helper.rb', line 74

def ROR_C(bits_x, shift) # A2.2.1
  raise ArgumentError unless shift != 0
  
  [bits_x.ror(shift), bits_x.rbit(0)]
end

#Shift_C(bits_value, type, amount, carry_in) ⇒ Object

A8.4.3

Raises:

  • (ArgumentError) 


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# File 'lib/indis-arm/instruction_helper.rb', line 55

def Shift_C(bits_value, type, amount, carry_in) # A8.4.3
  raise ArgumentError unless !(type == :SRType_RRX && amount != 1)
  
  return [bits_value, carry_in] if amount == 0
  
  case type
  when :SRType_LSL
    LSL_C(bits_value, amount)
  when :SRType_LSR
    LSR_C(bits_value, amount)
  when :SRType_ASR
    ASR_C(bits_value, amount)
  when :SRType_ROR
    ROR_C(bits_value, amount)
  when :SRType_RRX
    RRX_C(bits_value, carry_in)
  end   
end

#SignExtend(bits_x, i) ⇒ Object

P5.3



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# File 'lib/indis-arm/instruction_helper.rb', line 51

def SignExtend(bits_x, i) # P5.3
  bits_x.sign_extend(i)
end

#ZeroExtend(bits_x, i) ⇒ Object

P5.3



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# File 'lib/indis-arm/instruction_helper.rb', line 47

def ZeroExtend(bits_x, i) # P5.3
  bits_x.zero_extend(i)
end