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Improve flag shifts (MIPS)

This commit is contained in:
David Guillen Fandos 2021-09-25 23:26:08 +02:00
parent 9abb3ef934
commit 4dc706f361
2 changed files with 42 additions and 83 deletions
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53
psp/mips_emit.h
View File

@ -53,11 +53,6 @@ void execute_store_spsr(u32 new_spsr, u32 store_mask);
u32 execute_spsr_restore_body(u32 address);
u32 execute_store_cpsr_body(u32 _cpsr, u32 store_mask, u32 address);
u32 execute_lsl_flags_reg(u32 value, u32 shift);
u32 execute_lsr_flags_reg(u32 value, u32 shift);
u32 execute_asr_flags_reg(u32 value, u32 shift);
u32 execute_ror_flags_reg(u32 value, u32 shift);
typedef enum
{
mips_reg_zero,
@ -847,19 +842,55 @@ u32 arm_to_mips_reg[] =
reg_temp, arm_to_mips_reg[_rs]) \
#define generate_shift_reg_lsl_flags(_rm, _rs) \
{ \
u32 shift_reg = _rs; \
check_load_reg_pc(arm_reg_a1, shift_reg, 8); \
generate_load_reg_pc(reg_a0, _rm, 12); \
generate_load_reg_pc(reg_a1, _rs, 8); \
generate_function_call_swap_delay(execute_lsl_flags_reg) \
/* Only load the result on zero, no shift */ \
mips_emit_b(beq, arm_to_mips_reg[shift_reg], reg_zero, 7); \
generate_swap_delay(); \
mips_emit_addiu(reg_temp, arm_to_mips_reg[shift_reg], -1); \
mips_emit_sllv(reg_a0, reg_a0, reg_temp); \
mips_emit_srl(reg_c_cache, reg_a0, 31); \
mips_emit_sltiu(reg_temp, arm_to_mips_reg[shift_reg], 33); \
mips_emit_sll(reg_a0, reg_a0, 1); \
/* Result and flag to be zero if shift is 33+ */ \
mips_emit_movz(reg_c_cache, reg_zero, reg_temp); \
mips_emit_movz(reg_a0, reg_zero, reg_temp); \
} \
#define generate_shift_reg_lsr_flags(_rm, _rs) \
{ \
u32 shift_reg = _rs; \
check_load_reg_pc(arm_reg_a1, shift_reg, 8); \
generate_load_reg_pc(reg_a0, _rm, 12); \
generate_load_reg_pc(reg_a1, _rs, 8) \
generate_function_call_swap_delay(execute_lsr_flags_reg) \
/* Only load the result on zero, no shift */ \
mips_emit_b(beq, arm_to_mips_reg[shift_reg], reg_zero, 7); \
generate_swap_delay(); \
mips_emit_addiu(reg_temp, arm_to_mips_reg[shift_reg], -1); \
mips_emit_srlv(reg_a0, reg_a0, reg_temp); \
mips_emit_andi(reg_c_cache, reg_a0, 1); \
mips_emit_sltiu(reg_temp, arm_to_mips_reg[shift_reg], 33); \
mips_emit_srl(reg_a0, reg_a0, 1); \
/* Result and flag to be zero if shift is 33+ */ \
mips_emit_movz(reg_c_cache, reg_zero, reg_temp); \
mips_emit_movz(reg_a0, reg_zero, reg_temp); \
} \
#define generate_shift_reg_asr_flags(_rm, _rs) \
generate_load_reg_pc(reg_a1, _rs, 8); \
generate_load_reg_pc(reg_a0, _rm, 12); \
generate_load_reg_pc(reg_a1, _rs, 8) \
generate_function_call_swap_delay(execute_asr_flags_reg) \
/* Only load the result on zero, no shift */ \
mips_emit_b(beq, reg_a1, reg_zero, 7); \
generate_swap_delay(); \
/* Cap shift at 32, since it's equivalent */ \
mips_emit_addiu(reg_temp, reg_zero, 32); \
mips_emit_srl(reg_rv, reg_a1, 5); \
mips_emit_movn(reg_a1, reg_temp, reg_rv); \
mips_emit_addiu(reg_temp, reg_a1, -1); \
mips_emit_srav(reg_a0, reg_a0, reg_temp); \
mips_emit_andi(reg_c_cache, reg_a0, 1); \
mips_emit_sra(reg_a0, reg_a0, 1); \
#define generate_shift_reg_ror_flags(_rm, _rs) \
mips_emit_b(beq, arm_to_mips_reg[_rs], reg_zero, 3); \

72
psp/mips_stub.S
View File

@ -492,78 +492,6 @@ defsymbl(execute_store_spsr)
jr $ra # return
sw $4, SPSR_BASE($1) # spsr[cpu_mode] = $4 (delay slot)
# $4: value
# $5: shift
defsymbl(execute_lsl_flags_reg)
beq $5, $0, lsl_shift_zero # is the shift zero?
sltiu $1, $5, 32 # $1 = (shift < 32) (delay)
beq $1, $0, lsl_shift_high # is the shift >= 32?
li $2, 32
subu $2, $2, $5 # $2 = (32 - shift)
srlv $2, $4, $2 # $2 = (value >> (32 - shift))
andi $22, $2, 1 # c flag = (value >> (32 - shift)) & 0x01
lsl_shift_zero:
jr $ra # return
sllv $4, $4, $5 # return (value << shift) (delay)
lsl_shift_high:
sltiu $1, $5, 33 # $1 = (shift < 33) (delay)
bne $1, $0, lsl_shift_done # jump if shift == 32
andi $22, $4, 1 # c flag = value & 0x01 (delay)
addu $22, $0, $0 # c flag = 0 otherwise
lsl_shift_done:
jr $ra # return
addu $4, $0, $0 # value = 0 no matter what
defsymbl(execute_lsr_flags_reg)
beq $5, $0, lsr_shift_zero # is the shift zero?
sltiu $1, $5, 32 # $1 = (shift < 32) (delay)
beq $1, $0, lsr_shift_high # is the shift >= 32?
addiu $2, $5, -1 # $2 = shift - 1 (delay)
srlv $2, $4, $2 # $2 = (value >> (shift - 1))
andi $22, $2, 1 # c flag = (value >> (32 - shift)) & 0x01
lsr_shift_zero:
jr $ra # return
srlv $4, $4, $5 # return (value >> shift) (delay)
lsr_shift_high:
sltiu $1, $5, 33 # $1 = (shift < 33) (delay)
bne $1, $0, lsr_shift_done # jump if shift == 32
srl $22, $4, 31 # c flag = value >> 31 (delay)
addu $22, $0, $0 # c flag = 0 otherwise
lsr_shift_done:
jr $ra # return
addu $4, $0, $0 # value = 0 no matter what
defsymbl(execute_asr_flags_reg)
beq $5, $0, asr_shift_zero # is the shift zero?
sltiu $1, $5, 32 # $1 = (shift < 32) (delay)
beq $1, $0, asr_shift_high # is the shift >= 32?
addiu $2, $5, -1 # $2 = shift - 1 (delay)
srlv $2, $4, $2 # $2 = (value >> (shift - 1))
andi $22, $2, 1 # c flag = (value >> (32 - shift)) & 0x01
asr_shift_zero:
jr $ra # return
srav $4, $4, $5 # return (value >> shift) (delay)
asr_shift_high:
sra $4, $4, 31 # value >>= 31
jr $ra # return
andi $22, $4, 1 # c flag = value & 0x01
# $4: cycle counter argument
# $5: pointer to reg