Commit e0a42ebc authored by Edgar E. Iglesias's avatar Edgar E. Iglesias
Browse files

microblaze: Improve subkc



Move code from the helper into the translator. The remaining
helper parts can reuse helper_addkc, making it possible to
remove helper_subkc entirely.

Signed-off-by: default avatarEdgar E. Iglesias <edgar.iglesias@gmail.com>
parent 7e9e4330
......@@ -3,7 +3,6 @@
DEF_HELPER_1(raise_exception, void, i32)
DEF_HELPER_0(debug, void)
DEF_HELPER_FLAGS_3(addkc, TCG_CALL_PURE | TCG_CALL_CONST, i32, i32, i32, i32)
DEF_HELPER_4(subkc, i32, i32, i32, i32, i32)
DEF_HELPER_2(cmp, i32, i32, i32)
DEF_HELPER_2(cmpu, i32, i32, i32)
......
......@@ -138,28 +138,6 @@ uint32_t helper_addkc(uint32_t a, uint32_t b, uint32_t cf)
return ncf;
}
uint32_t helper_subkc(uint32_t a, uint32_t b, uint32_t k, uint32_t c)
{
uint32_t d, cf = 1, ncf;
if (c)
cf = env->sregs[SR_MSR] >> 31;
assert(cf == 0 || cf == 1);
d = b + ~a + cf;
if (!k) {
ncf = compute_carry(b, ~a, cf);
assert(ncf == 0 || ncf == 1);
if (ncf)
env->sregs[SR_MSR] |= MSR_C | MSR_CC;
else
env->sregs[SR_MSR] &= ~(MSR_C | MSR_CC);
}
D(qemu_log("%x = %x + %x cf=%d ncf=%d k=%d c=%d\n",
d, a, b, cf, ncf, k, c));
return d;
}
static inline int div_prepare(uint32_t a, uint32_t b)
{
if (b == 0) {
......
......@@ -247,6 +247,7 @@ static void dec_add(DisasContext *dc)
static void dec_sub(DisasContext *dc)
{
unsigned int u, cmp, k, c;
TCGv cf, na;
u = dc->imm & 2;
k = dc->opcode & 4;
......@@ -261,24 +262,57 @@ static void dec_sub(DisasContext *dc)
else
gen_helper_cmp(cpu_R[dc->rd], cpu_R[dc->ra], cpu_R[dc->rb]);
}
} else {
LOG_DIS("sub%s%s r%d, r%d r%d\n",
k ? "k" : "", c ? "c" : "", dc->rd, dc->ra, dc->rb);
return;
}
if (!k || c) {
TCGv t;
t = tcg_temp_new();
if (dc->rd)
gen_helper_subkc(cpu_R[dc->rd], cpu_R[dc->ra], *(dec_alu_op_b(dc)),
tcg_const_tl(k), tcg_const_tl(c));
else
gen_helper_subkc(t, cpu_R[dc->ra], *(dec_alu_op_b(dc)),
tcg_const_tl(k), tcg_const_tl(c));
tcg_temp_free(t);
}
else if (dc->rd)
LOG_DIS("sub%s%s r%d, r%d r%d\n",
k ? "k" : "", c ? "c" : "", dc->rd, dc->ra, dc->rb);
/* Take care of the easy cases first. */
if (k) {
/* k - keep carry, no need to update MSR. */
/* If rd == r0, it's a nop. */
if (dc->rd) {
tcg_gen_sub_tl(cpu_R[dc->rd], *(dec_alu_op_b(dc)), cpu_R[dc->ra]);
if (c) {
/* c - Add carry into the result. */
cf = tcg_temp_new();
read_carry(dc, cf);
tcg_gen_add_tl(cpu_R[dc->rd], cpu_R[dc->rd], cf);
tcg_temp_free(cf);
}
}
return;
}
/* From now on, we can assume k is zero. So we need to update MSR. */
/* Extract carry. And complement a into na. */
cf = tcg_temp_new();
na = tcg_temp_new();
if (c) {
read_carry(dc, cf);
} else {
tcg_gen_movi_tl(cf, 1);
}
/* d = b + ~a + c. carry defaults to 1. */
tcg_gen_not_tl(na, cpu_R[dc->ra]);
if (dc->rd) {
TCGv ncf = tcg_temp_new();
gen_helper_addkc(ncf, na, *(dec_alu_op_b(dc)), cf);
tcg_gen_add_tl(cpu_R[dc->rd], na, *(dec_alu_op_b(dc)));
tcg_gen_add_tl(cpu_R[dc->rd], cpu_R[dc->rd], cf);
write_carry(dc, ncf);
tcg_temp_free(ncf);
} else {
gen_helper_addkc(cf, na, *(dec_alu_op_b(dc)), cf);
write_carry(dc, cf);
}
tcg_temp_free(cf);
tcg_temp_free(na);
}
static void dec_pattern(DisasContext *dc)
......
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