mirror of https://github.com/lefticus/6502-cpp.git
54 lines
1.1 KiB
C++
54 lines
1.1 KiB
C++
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static constexpr std::string_view __mulhi3 =
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R"(
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;;; based on protocol from gcc's calling conventions for AVR
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;;; 16x16 = 16 multiply
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;;; R25:R24 = R23:R22 * R25:R24
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;;; Clobbers: __tmp_reg__, R21..R23
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__mulhi3:
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mov __temp_reg__,r24
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mov r21,r25
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ldi r25,0
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ldi r24,0
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cp __temp_reg__,__zero_reg__
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cpc r21,__zero_reg__
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breq .__mulhi3_L5
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.__mulhi3_L4:
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sbrs __temp_reg__,0
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rjmp .__mulhi3_L3
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add r24,r22
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adc r25,r23
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.__mulhi3_L3:
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lsr r21
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ror __temp_reg__
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lsl r22
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rol r23
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cp __temp_reg__,__zero_reg__
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cpc r21,__zero_reg__
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brne .__mulhi3_L4
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ret
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.__mulhi3_L5:
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ret
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)";
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static constexpr std::string_view __mulqi3 =
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R"(
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;;; based on protocol from gcc's calling conventions for AVR
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;;; 8x8 = 8 multiply
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;;; R24 = R22 * R24
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;;; Clobbers: __tmp_reg__, R22, R24
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__mulqi3:
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ldi __temp_reg__,0
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__mulqi_1:
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sbrc r24,0
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add __temp_reg__,r22
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lsr r24
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lsl r22
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cpse r24,__zero_reg__
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rjmp __mulqi_1
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mov r24, __temp_reg__
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ret
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)"; |