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6502-cpp/include/lib1funcs.hpp
2021-05-27 08:31:02 -06:00

54 lines
1.1 KiB
C++

static constexpr std::string_view __mulhi3 =
R"(
;;; based on protocol from gcc's calling conventions for AVR
;;; 16x16 = 16 multiply
;;; R25:R24 = R23:R22 * R25:R24
;;; Clobbers: __tmp_reg__, R21..R23
__mulhi3:
mov __temp_reg__,r24
mov r21,r25
ldi r25,0
ldi r24,0
cp __temp_reg__,__zero_reg__
cpc r21,__zero_reg__
breq .__mulhi3_L5
.__mulhi3_L4:
sbrs __temp_reg__,0
rjmp .__mulhi3_L3
add r24,r22
adc r25,r23
.__mulhi3_L3:
lsr r21
ror __temp_reg__
lsl r22
rol r23
cp __temp_reg__,__zero_reg__
cpc r21,__zero_reg__
brne .__mulhi3_L4
ret
.__mulhi3_L5:
ret
)";
static constexpr std::string_view __mulqi3 =
R"(
;;; based on protocol from gcc's calling conventions for AVR
;;; 8x8 = 8 multiply
;;; R24 = R22 * R24
;;; Clobbers: __tmp_reg__, R22, R24
__mulqi3:
ldi __temp_reg__,0
__mulqi_1:
sbrc r24,0
add __temp_reg__,r22
lsr r24
lsl r22
cpse r24,__zero_reg__
rjmp __mulqi_1
mov r24, __temp_reg__
ret
)";