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Fix constant optimization and fused instruction
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1. Fix tailcall updating in fused instructions
2. Fix errors in constant optimization

Close: #228
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@qwe661234
qwe661234 committed Sep 26, 2023
1 parent 9f63962 commit 0746a40
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Showing 2 changed files with 22 additions and 18 deletions.
18 changes: 10 additions & 8 deletions src/emulate.c
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Original file line number Diff line number Diff line change
Expand Up @@ -926,6 +926,7 @@ static void match_pattern(block_t *block)
ir->rs2 = next_ir->rd;
ir->rs1 = next_ir->rs1;
ir->impl = dispatch_table[ir->opcode];
ir->tailcall = next_ir->tailcall;
} else if (next_ir->opcode == rv_insn_add &&
ir->rd == next_ir->rs1) {
/* The destination register of the LUI instruction is the
Expand All @@ -935,21 +936,22 @@ static void match_pattern(block_t *block)
ir->rs2 = next_ir->rd;
ir->rs1 = next_ir->rs2;
ir->impl = dispatch_table[ir->opcode];
} else {
ir->tailcall = next_ir->tailcall;
} else if (next_ir->opcode == rv_insn_lui) {
count = 1;
next_ir = ir + 1;
while (1) {
if (next_ir->opcode != rv_insn_lui)
break;
next_ir->opcode = rv_insn_nop;
count++;
next_ir += 1;
}
if (count > 1) {
ir->imm2 = count;
ir->opcode = rv_insn_fuse1;
ir->impl = dispatch_table[ir->opcode];
if (next_ir->tailcall)
break;
next_ir++;
}
ir->imm2 = count;
ir->opcode = rv_insn_fuse1;
ir->impl = dispatch_table[ir->opcode];
ir->tailcall = next_ir->tailcall;
}
break;

Expand Down
22 changes: 12 additions & 10 deletions src/rv32_constopt.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -443,8 +443,8 @@ CONSTOPT(mulh, {
if (constopt_info->is_constant[ir->rs1] &&
constopt_info->is_constant[ir->rs2]) {
constopt_info->is_constant[ir->rd] = true;
const int64_t a = constopt_info->const_val[ir->rs1];
const int64_t b = constopt_info->const_val[ir->rs2];
const int64_t a = (int32_t) constopt_info->const_val[ir->rs1];
const int64_t b = (int32_t) constopt_info->const_val[ir->rs2];
ir->imm = ((uint64_t) (a * b)) >> 32;
constopt_info->const_val[ir->rd] = ir->imm;
ir->opcode = rv_insn_lui;
Expand All @@ -457,7 +457,6 @@ CONSTOPT(mulh, {
CONSTOPT(mulhsu, {
if (constopt_info->is_constant[ir->rs1] &&
constopt_info->is_constant[ir->rs2]) {
printf("OPT MUL\n");
constopt_info->is_constant[ir->rd] = true;
const int64_t a = (int32_t) constopt_info->const_val[ir->rs1];
const int64_t b = constopt_info->const_val[ir->rs2];
Expand Down Expand Up @@ -757,7 +756,7 @@ CONSTOPT(csw, {})
CONSTOPT(caddi, {
if (constopt_info->is_constant[ir->rd]) {
constopt_info->is_constant[ir->rd] = true;
ir->imm = constopt_info->const_val[ir->rd] + (uint16_t) ir->imm;
ir->imm = constopt_info->const_val[ir->rd] + (int16_t) ir->imm;
constopt_info->const_val[ir->rd] = ir->imm;
ir->opcode = rv_insn_clui;
ir->impl = dispatch_table[ir->opcode];
Expand All @@ -768,7 +767,7 @@ CONSTOPT(caddi, {
/* C.JAL */
CONSTOPT(cjal, {
constopt_info->is_constant[rv_reg_ra] = true;
constopt_info->const_val[ir->rd] = ir->pc + ir->insn_len;
constopt_info->const_val[rv_reg_ra] = ir->pc + ir->insn_len;
})

/* C.LI loads the sign-extended 6-bit immediate, imm, into register rd.
Expand Down Expand Up @@ -817,7 +816,8 @@ CONSTOPT(csrli, {
if (constopt_info->is_constant[ir->rs1]) {
constopt_info->is_constant[ir->rs1] = true;
ir->imm = constopt_info->const_val[ir->rs1] >> ir->shamt;
constopt_info->const_val[ir->rd] = ir->imm;
constopt_info->const_val[ir->rs1] = ir->imm;
ir->rd = ir->rs1;
ir->opcode = rv_insn_clui;
ir->impl = dispatch_table[ir->opcode];
} else
Expand All @@ -834,7 +834,8 @@ CONSTOPT(csrai, {
ir->imm = constopt_info->const_val[ir->rs1] >> ir->shamt;
for (unsigned int i = 0; i < ir->shamt; ++i)
ir->imm |= mask >> i;
constopt_info->const_val[ir->rd] = ir->imm;
constopt_info->const_val[ir->rs1] = ir->imm;
ir->rd = ir->rs1;
ir->opcode = rv_insn_clui;
ir->impl = dispatch_table[ir->opcode];
} else
Expand All @@ -848,8 +849,9 @@ CONSTOPT(csrai, {
CONSTOPT(candi, {
if (constopt_info->is_constant[ir->rs1]) {
constopt_info->is_constant[ir->rs1] = true;
ir->imm = constopt_info->const_val[ir->rs1] & ir->shamt;
constopt_info->const_val[ir->rd] = ir->imm;
ir->imm = constopt_info->const_val[ir->rs1] & ir->imm;
constopt_info->const_val[ir->rs1] = ir->imm;
ir->rd = ir->rs1;
ir->opcode = rv_insn_clui;
ir->impl = dispatch_table[ir->opcode];
} else
Expand Down Expand Up @@ -948,7 +950,7 @@ CONSTOPT(cbnez, {
CONSTOPT(cslli, {
if (constopt_info->is_constant[ir->rd]) {
constopt_info->is_constant[ir->rd] = true;
ir->imm = constopt_info->const_val[ir->rs2] << (uint8_t) ir->imm;
ir->imm = constopt_info->const_val[ir->rd] << (uint8_t) ir->imm;
constopt_info->const_val[ir->rd] = ir->imm;
ir->opcode = rv_insn_clui;
ir->impl = dispatch_table[ir->opcode];
Expand Down

1 comment on commit 0746a40

@jserv
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@jserv jserv commented on 0746a40 Sep 26, 2023

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Benchmarks

Benchmark suite Current: 0746a40 Previous: 54f986f Ratio
Dhrystone 1064.77 Average DMIPS over 10 runs 1058.12 Average DMIPS over 10 runs 0.99
Coremark 933.034 Average iterations/sec over 10 runs 922.773 Average iterations/sec over 10 runs 0.99

This comment was automatically generated by workflow using github-action-benchmark.

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