Tested spec2017 performance in Sierra Forest, Icelake, CascadeLake, at least
there is no obvious regression.
Bootstrapped and regtested on x86_64-pc-linux-gnu{-m32,}.
OK for trunk?
gcc/ChangeLog:
* config/i386/x86-tune-costs.h (struct processor_costs):
Adjust rtx_cost of imulq and imulw for COST_N_INSNS (4)
to COST_N_INSNS (3).
gcc/testsuite/ChangeLog:
* gcc.target/i386/pr115749.c: New test.
---
gcc/config/i386/x86-tune-costs.h | 16 ++++++++--------
gcc/testsuite/gcc.target/i386/pr115749.c | 16 ++++++++++++++++
2 files changed, 24 insertions(+), 8 deletions(-) create mode 100644
gcc/testsuite/gcc.target/i386/pr115749.c
diff --git a/gcc/config/i386/x86-tune-costs.h b/gcc/config/i386/x86-tune-costs.h
index 769f334e531..2bfaee554d5 100644
--- a/gcc/config/i386/x86-tune-costs.h
+++ b/gcc/config/i386/x86-tune-costs.h
@@ -2182,7 +2182,7 @@ struct processor_costs skylake_cost = {
COSTS_N_INSNS (1), /* variable shift costs */
COSTS_N_INSNS (1), /* constant shift costs */
{COSTS_N_INSNS (3), /* cost of starting multiply for QI */
- COSTS_N_INSNS (4), /* HI */
+ COSTS_N_INSNS (3), /* HI */
COSTS_N_INSNS (3), /* SI */
COSTS_N_INSNS (3), /* DI */
COSTS_N_INSNS (3)}, /* other */
@@ -2310,7 +2310,7 @@ struct processor_costs icelake_cost = {
COSTS_N_INSNS (1), /* variable shift costs */
COSTS_N_INSNS (1), /* constant shift costs */
{COSTS_N_INSNS (3), /* cost of starting multiply for QI */
- COSTS_N_INSNS (4), /* HI */
+ COSTS_N_INSNS (3), /* HI */
COSTS_N_INSNS (3), /* SI */
COSTS_N_INSNS (3), /* DI */
COSTS_N_INSNS (3)}, /* other */
@@ -2434,9 +2434,9 @@ struct processor_costs alderlake_cost = {
COSTS_N_INSNS (1), /* variable shift costs */
COSTS_N_INSNS (1), /* constant shift costs */
{COSTS_N_INSNS (3), /* cost of starting multiply for QI */
- COSTS_N_INSNS (4), /* HI */
+ COSTS_N_INSNS (3), /* HI */
COSTS_N_INSNS (3), /* SI */
- COSTS_N_INSNS (4), /* DI */
+ COSTS_N_INSNS (3), /* DI */
COSTS_N_INSNS (4)}, /* other */
0, /* cost of multiply per each bit set */
{COSTS_N_INSNS (16), /* cost of a divide/mod for QI */
@@ -3234,9 +3234,9 @@ struct processor_costs tremont_cost = {
COSTS_N_INSNS (1), /* variable shift costs */
COSTS_N_INSNS (1), /* constant shift costs */
{COSTS_N_INSNS (3), /* cost of starting multiply for QI */
- COSTS_N_INSNS (4), /* HI */
+ COSTS_N_INSNS (3), /* HI */
COSTS_N_INSNS (3), /* SI */
- COSTS_N_INSNS (4), /* DI */
+ COSTS_N_INSNS (3), /* DI */
COSTS_N_INSNS (4)}, /* other */
0, /* cost of multiply per each bit set */
{COSTS_N_INSNS (16), /* cost of a divide/mod for QI */
@@ -3816,9 +3816,9 @@ struct processor_costs generic_cost = {
COSTS_N_INSNS (1), /* variable shift costs */
COSTS_N_INSNS (1), /* constant shift costs */
{COSTS_N_INSNS (3), /* cost of starting multiply for QI */
- COSTS_N_INSNS (4), /* HI */
+ COSTS_N_INSNS (3), /* HI */
COSTS_N_INSNS (3), /* SI */
- COSTS_N_INSNS (4), /* DI */
+ COSTS_N_INSNS (3), /* DI */
COSTS_N_INSNS (4)}, /* other */
0, /* cost of multiply per each bit set */
{COSTS_N_INSNS (16), /* cost of a divide/mod for QI */
diff --git a/gcc/testsuite/gcc.target/i386/pr115749.c
b/gcc/testsuite/gcc.target/i386/pr115749.c
new file mode 100644
index 00000000000..82505d603ef
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr115749.c
@@ -0,0 +1,16 @@
+/* PR target/115749 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -mtune=generic" } */
+/* { dg-final { scan-assembler-times "imul" 2 } } */
+/* { dg-final { scan-assembler-not "sal" } } */
+
+unsigned long func(unsigned long x)
+{
+ return x % 240;
+}
+
+unsigned short func2(unsigned short x)
+{
+ return x * 240;
+}
+
--
2.31.1
