microblaze: Improve addkc
* Optimize handling when carry is not updated.
* Optimize handling for adds with nop semantics.
* Move code from helper_addkc to the translator making
helper_addkc PURE and CONST.
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
diff --git a/target-microblaze/helper.h b/target-microblaze/helper.h
index 11ad1b6..4871406 100644
--- a/target-microblaze/helper.h
+++ b/target-microblaze/helper.h
@@ -2,7 +2,7 @@
DEF_HELPER_1(raise_exception, void, i32)
DEF_HELPER_0(debug, void)
-DEF_HELPER_4(addkc, i32, i32, i32, i32, i32)
+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)
diff --git a/target-microblaze/op_helper.c b/target-microblaze/op_helper.c
index 97461ae..eb5a8b7 100644
--- a/target-microblaze/op_helper.c
+++ b/target-microblaze/op_helper.c
@@ -128,26 +128,14 @@
return t;
}
-uint32_t helper_addkc(uint32_t a, uint32_t b, uint32_t k, uint32_t c)
+uint32_t helper_addkc(uint32_t a, uint32_t b, uint32_t cf)
{
- uint32_t d, cf = 0, ncf;
+ uint32_t d, ncf;
- if (c)
- cf = env->sregs[SR_MSR] >> 31;
- assert(cf == 0 || cf == 1);
d = a + b + cf;
- if (!k) {
- ncf = compute_carry(a, b, 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;
+ ncf = compute_carry(a, b, cf);
+ return ncf;
}
uint32_t helper_subkc(uint32_t a, uint32_t b, uint32_t k, uint32_t c)
diff --git a/target-microblaze/translate.c b/target-microblaze/translate.c
index dd2865c..d983c8b 100644
--- a/target-microblaze/translate.c
+++ b/target-microblaze/translate.c
@@ -193,6 +193,7 @@
static void dec_add(DisasContext *dc)
{
unsigned int k, c;
+ TCGv cf;
k = dc->opcode & 4;
c = dc->opcode & 2;
@@ -201,17 +202,47 @@
dc->type_b ? "i" : "", k ? "k" : "", c ? "c" : "",
dc->rd, dc->ra, dc->rb);
- if (k && !c && dc->rd)
- tcg_gen_add_tl(cpu_R[dc->rd], cpu_R[dc->ra], *(dec_alu_op_b(dc)));
- else if (dc->rd)
- gen_helper_addkc(cpu_R[dc->rd], cpu_R[dc->ra], *(dec_alu_op_b(dc)),
- tcg_const_tl(k), tcg_const_tl(c));
- else {
- TCGv d = tcg_temp_new();
- gen_helper_addkc(d, cpu_R[dc->ra], *(dec_alu_op_b(dc)),
- tcg_const_tl(k), tcg_const_tl(c));
- tcg_temp_free(d);
+ /* 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_add_tl(cpu_R[dc->rd], cpu_R[dc->ra], *(dec_alu_op_b(dc)));
+
+ 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. */
+ cf = tcg_temp_new();
+ if (c) {
+ read_carry(dc, cf);
+ } else {
+ tcg_gen_movi_tl(cf, 0);
+ }
+
+ if (dc->rd) {
+ TCGv ncf = tcg_temp_new();
+ gen_helper_addkc(ncf, cpu_R[dc->ra], *(dec_alu_op_b(dc)), cf);
+ tcg_gen_add_tl(cpu_R[dc->rd], cpu_R[dc->ra], *(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, cpu_R[dc->ra], *(dec_alu_op_b(dc)),
+ tcg_const_tl(cf));
+ write_carry(dc, cf);
+ }
+ tcg_temp_free(cf);
}
static void dec_sub(DisasContext *dc)
