py/asmrv32: Refactor register-indexed load/store emitters.

This commit shortens register-indexed load/store emitter functions, by
reusing integer-indexed equivalent operations as part of the sequence
generation process.

Before these changes, register-indexed load/store emitters would follow
two steps to generate the sequence: generate opcodes to fix up the
register offset to make it point to the exact position in memory where
the operation should take place, and then perform the load/store
operation itself using 0 as an offset from the recalculated address
register.

Since there is already a generic optimised emitter for integer-indexed
load/stores, that bit of code can be reused rather than having an ad-hoc
implementation that is tailored to operate on an offset of 0.  Removing
the custom emitter code in favour of calling the general integer-indexed
emitter saves around 150 bytes without any changes in the emitter
behaviour (generating the same opcode sequence and making use of future
improvement in that emitter too).

Signed-off-by: Alessandro Gatti <a.gatti@frob.it>

Author: agatti

py/asmrv32.c

@@ -577,24 +577,12 @@ static void asm_rv32_fix_up_scaled_reg_reg_reg(asm_rv32_t *state, mp_uint_t rs1,
 
 void asm_rv32_emit_load_reg_reg_reg(asm_rv32_t *state, mp_uint_t rd, mp_uint_t rs1, mp_uint_t rs2, mp_uint_t operation_size) {
     asm_rv32_fix_up_scaled_reg_reg_reg(state, rs1, rs2, operation_size);
-    if (operation_size == 2 && RV32_IS_IN_C_REGISTER_WINDOW(rd) && RV32_IS_IN_C_REGISTER_WINDOW(rs1)) {
-        // c.lw rd', offset(rs')
-        asm_rv32_opcode_clw(state, RV32_MAP_IN_C_REGISTER_WINDOW(rd), RV32_MAP_IN_C_REGISTER_WINDOW(rs1), 0);
-    } else {
-        // lbu|lhu|lw rd, offset(rs)
-        asm_rv32_emit_word_opcode(state, RV32_ENCODE_TYPE_I(0x03, RV32_LOAD_OPCODE_TABLE[operation_size], rd, rs1, 0));
-    }
+    asm_rv32_emit_load_reg_reg_offset(state, rd, rs1, 0, operation_size);
 }
 
 void asm_rv32_emit_store_reg_reg_reg(asm_rv32_t *state, mp_uint_t rd, mp_uint_t rs1, mp_uint_t rs2, mp_uint_t operation_size) {
     asm_rv32_fix_up_scaled_reg_reg_reg(state, rs1, rs2, operation_size);
-    if (operation_size == 2 && RV32_IS_IN_C_REGISTER_WINDOW(rd) && RV32_IS_IN_C_REGISTER_WINDOW(rs1)) {
-        // c.sw rd', offset(rs')
-        asm_rv32_opcode_csw(state, RV32_MAP_IN_C_REGISTER_WINDOW(rd), RV32_MAP_IN_C_REGISTER_WINDOW(rs1), 0);
-    } else {
-        // sb|sh|sw rd, offset(rs)
-        asm_rv32_emit_word_opcode(state, RV32_ENCODE_TYPE_S(0x23, operation_size, rs1, rd, 0));
-    }
+    asm_rv32_emit_store_reg_reg_offset(state, rd, rs1, 0, operation_size);
 }
 
 void asm_rv32_meta_comparison_eq(asm_rv32_t *state, mp_uint_t rs1, mp_uint_t rs2, mp_uint_t rd) {