diff options
| -rw-r--r-- | py/asmrv32.c | 69 | ||||
| -rw-r--r-- | py/asmrv32.h | 4 |
2 files changed, 39 insertions, 34 deletions
diff --git a/py/asmrv32.c b/py/asmrv32.c index 7dd58beca..a68401cf3 100644 --- a/py/asmrv32.c +++ b/py/asmrv32.c @@ -132,9 +132,9 @@ static void split_immediate(mp_int_t immediate, mp_uint_t *upper, mp_uint_t *low static void load_upper_immediate(asm_rv32_t *state, mp_uint_t rd, mp_uint_t immediate) { // if immediate fits in 17 bits and is ≠ 0: - // c.lui rd, HI(immediate) + // c.lui rd, HI(immediate) // else: - // lui rd, HI(immediate) + // lui rd, HI(immediate) if (FIT_SIGNED(immediate, 17) && ((immediate >> 12) != 0)) { asm_rv32_opcode_clui(state, rd, immediate); } else { @@ -270,6 +270,14 @@ static void emit_function_epilogue(asm_rv32_t *state, mp_uint_t registers) { state->saved_registers_mask = old_saved_registers_mask; } +static bool calculate_displacement_for_label(asm_rv32_t *state, mp_uint_t label, ptrdiff_t *displacement) { + assert(displacement != NULL && "Displacement pointer is NULL"); + + mp_uint_t label_offset = state->base.label_offsets[label]; + *displacement = (ptrdiff_t)(label_offset - state->base.code_offset); + return (label_offset != (mp_uint_t)-1) && (*displacement < 0); +} + /////////////////////////////////////////////////////////////////////////////// void asm_rv32_entry(asm_rv32_t *state, mp_uint_t locals) { @@ -326,10 +334,10 @@ void asm_rv32_emit_call_ind(asm_rv32_t *state, mp_uint_t index) { } void asm_rv32_emit_jump_if_reg_eq(asm_rv32_t *state, mp_uint_t rs1, mp_uint_t rs2, mp_uint_t label) { - ptrdiff_t displacement = (ptrdiff_t)(state->base.label_offsets[label] - state->base.code_offset); + ptrdiff_t displacement = 0; + bool can_emit_short_jump = calculate_displacement_for_label(state, label, &displacement); - // The least significant bit is ignored anyway. - if (FIT_SIGNED(displacement, 13)) { + if (can_emit_short_jump && FIT_SIGNED(displacement, 13)) { // beq rs1, rs2, displacement asm_rv32_opcode_beq(state, rs1, rs2, displacement); return; @@ -354,31 +362,24 @@ void asm_rv32_emit_jump_if_reg_eq(asm_rv32_t *state, mp_uint_t rs1, mp_uint_t rs } void asm_rv32_emit_jump_if_reg_nonzero(asm_rv32_t *state, mp_uint_t rs, mp_uint_t label) { - ptrdiff_t displacement = (ptrdiff_t)(state->base.label_offsets[label] - state->base.code_offset); + ptrdiff_t displacement = 0; + bool can_emit_short_jump = calculate_displacement_for_label(state, label, &displacement); - if (FIT_SIGNED(displacement, 9) && IS_IN_C_REGISTER_WINDOW(rs)) { + if (can_emit_short_jump && FIT_SIGNED(displacement, 8) && IS_IN_C_REGISTER_WINDOW(rs)) { // c.bnez rs', displacement asm_rv32_opcode_cbnez(state, MAP_IN_C_REGISTER_WINDOW(rs), displacement); return; } - // The least significant bit is ignored anyway. - if (FIT_SIGNED(displacement, 13)) { + if (can_emit_short_jump && FIT_SIGNED(displacement, 13)) { // bne rs, zero, displacement asm_rv32_opcode_bne(state, rs, ASM_RV32_REG_ZERO, displacement); return; } - // Compensate for the initial C.BEQZ/BEQ opcode. - displacement -= IS_IN_C_REGISTER_WINDOW(rs) ? ASM_HALFWORD_SIZE : ASM_WORD_SIZE; - - mp_uint_t upper = 0; - mp_uint_t lower = 0; - split_immediate(displacement, &upper, &lower); - // TODO: Can this clobber REG_TEMP[0:2]? - // if rs1 in C window (the offset always fits): + // if rs1 in C window and displacement is negative: // c.beqz rs', 10 ; PC + 0 // auipc temporary, HI(displacement) ; PC + 2 // jalr zero, temporary, LO(displacement) ; PC + 6 @@ -388,11 +389,20 @@ void asm_rv32_emit_jump_if_reg_nonzero(asm_rv32_t *state, mp_uint_t rs, mp_uint_ // auipc temporary, HI(displacement) ; PC + 4 // jalr zero, temporary, LO(displacement) ; PC + 8 // ... ; PC + 12 - if (IS_IN_C_REGISTER_WINDOW(rs)) { + + if (can_emit_short_jump && IS_IN_C_REGISTER_WINDOW(rs)) { asm_rv32_opcode_cbeqz(state, MAP_IN_C_REGISTER_WINDOW(rs), 10); + // Compensate for the C.BEQZ opcode. + displacement -= ASM_HALFWORD_SIZE; } else { asm_rv32_opcode_beq(state, rs, ASM_RV32_REG_ZERO, 12); + // Compensate for the BEQ opcode. + displacement -= ASM_WORD_SIZE; } + + mp_uint_t upper = 0; + mp_uint_t lower = 0; + split_immediate(displacement, &upper, &lower); asm_rv32_opcode_auipc(state, INTERNAL_TEMPORARY, upper); asm_rv32_opcode_jalr(state, ASM_RV32_REG_ZERO, INTERNAL_TEMPORARY, lower); } @@ -502,10 +512,10 @@ void asm_rv32_emit_load_reg_reg_offset(asm_rv32_t *state, mp_uint_t rd, mp_uint_ } void asm_rv32_emit_jump(asm_rv32_t *state, mp_uint_t label) { - ptrdiff_t displacement = (ptrdiff_t)(state->base.label_offsets[label] - state->base.code_offset); + ptrdiff_t displacement = 0; + bool can_emit_short_jump = calculate_displacement_for_label(state, label, &displacement); - // The least significant bit is ignored anyway. - if (FIT_SIGNED(displacement, 13)) { + if (can_emit_short_jump && FIT_SIGNED(displacement, 12)) { // c.j displacement asm_rv32_opcode_cj(state, displacement); return; @@ -536,12 +546,12 @@ void asm_rv32_emit_store_reg_reg_offset(asm_rv32_t *state, mp_uint_t rd, mp_uint mp_uint_t lower = 0; split_immediate(scaled_offset, &upper, &lower); - // lui rd, HI(offset) ; Or c.lui if possible - // c.add rd, rs - // sw rd, LO(offset)(rd) - load_upper_immediate(state, rd, upper); - asm_rv32_opcode_cadd(state, rd, rs); - asm_rv32_opcode_sw(state, rd, rd, lower); + // lui temporary, HI(offset) ; Or c.lui if possible + // c.add temporary, rs + // sw rd, LO(offset)(temporary) + load_upper_immediate(state, INTERNAL_TEMPORARY, upper); + asm_rv32_opcode_cadd(state, INTERNAL_TEMPORARY, rs); + asm_rv32_opcode_sw(state, rd, INTERNAL_TEMPORARY, lower); } void asm_rv32_emit_mov_reg_pcrel(asm_rv32_t *state, mp_uint_t rd, mp_uint_t label) { @@ -550,11 +560,6 @@ void asm_rv32_emit_mov_reg_pcrel(asm_rv32_t *state, mp_uint_t rd, mp_uint_t labe mp_uint_t lower = 0; split_immediate(displacement, &upper, &lower); - // Compressed instructions are not used even if they may allow for code size - // savings as the code changes size between compute and emit passes - // otherwise. If that happens then the assertion at asmbase.c:93 triggers - // when built in debug mode. - // auipc rd, HI(relative) // addi rd, rd, LO(relative) asm_rv32_opcode_auipc(state, rd, upper); diff --git a/py/asmrv32.h b/py/asmrv32.h index 77a5b0ab6..775cf1ffc 100644 --- a/py/asmrv32.h +++ b/py/asmrv32.h @@ -331,7 +331,7 @@ static inline void asm_rv32_opcode_lw(asm_rv32_t *state, mp_uint_t rd, mp_uint_t } // MUL RD, RS1, RS2 -static inline void asm_rv32m_opcode_mul(asm_rv32_t *state, mp_uint_t rd, mp_uint_t rs1, mp_uint_t rs2) { +static inline void asm_rv32_opcode_mul(asm_rv32_t *state, mp_uint_t rd, mp_uint_t rs1, mp_uint_t rs2) { // R: 0000001 ..... ..... 000 ..... 0110011 asm_rv32_emit_word_opcode(state, RV32_ENCODE_TYPE_R(0x33, 0x00, 0x01, rd, rs1, rs2)); } @@ -479,7 +479,7 @@ void asm_rv32_emit_store_reg_reg_offset(asm_rv32_t *state, mp_uint_t source, mp_ #define ASM_MOV_REG_LOCAL(state, rd, local) asm_rv32_emit_mov_reg_local(state, rd, local) #define ASM_MOV_REG_PCREL(state, rd, label) asm_rv32_emit_mov_reg_pcrel(state, rd, label) #define ASM_MOV_REG_REG(state, rd, rs) asm_rv32_opcode_cmv(state, rd, rs) -#define ASM_MUL_REG_REG(state, rd, rs) asm_rv32m_opcode_mul(state, rd, rd, rs) +#define ASM_MUL_REG_REG(state, rd, rs) asm_rv32_opcode_mul(state, rd, rd, rs) #define ASM_NEG_REG(state, rd) asm_rv32_opcode_sub(state, rd, ASM_RV32_REG_ZERO, rd) #define ASM_NOT_REG(state, rd) asm_rv32_opcode_xori(state, rd, rd, -1) #define ASM_OR_REG_REG(state, rd, rs) asm_rv32_opcode_or(state, rd, rd, rs) |