There is an obvious fusion bug that is exposed by more VLS patterns support.
After more VLS modes support, it cause following FAILs:
FAIL: gcc.target/riscv/rvv/autovec/reduc/reduc_run-2.c execution test
FAIL: gcc.target/riscv/rvv/autovec/reduc/reduc_run-2.c execution test
FAIL: gcc.target/riscv/rvv/autovec/reduc/reduc_run-2.c execution test
FAIL: gcc.target/riscv/rvv/autovec/reduc/reduc_run-2.c execution test
Demand 1: SEW = 64, LMUL = 1, RATIO = 64, demand SEW, demand GE_SEW.
Demand 2: SEW = 64, LMUL = 2, RATIO = 32, demand SEW, demand GE_SEW, demand
RATIO.
Before this patch:
merge demand: SEW = 64, LMUL = 1, RATIO = 32, demand SEW, demand LMUL, demand
GE_SEW.
It's obvious incorrect of merge LMUL which should be new LMUL = (demand 2 RATIO
* greatest SEW) = M2
gcc/ChangeLog:
* config/riscv/riscv-vsetvl.cc (vlmul_for_greatest_sew_second_ratio):
New function.
* config/riscv/riscv-vsetvl.def (DEF_SEW_LMUL_FUSE_RULE): Fix bug.
---
gcc/config/riscv/riscv-vsetvl.cc | 8 ++++++++
gcc/config/riscv/riscv-vsetvl.def | 4 ++--
2 files changed, 10 insertions(+), 2 deletions(-)
diff --git a/gcc/config/riscv/riscv-vsetvl.cc b/gcc/config/riscv/riscv-vsetvl.cc
index 5f031c18df5..df980b6770e 100644
--- a/gcc/config/riscv/riscv-vsetvl.cc
+++ b/gcc/config/riscv/riscv-vsetvl.cc
@@ -1308,6 +1308,14 @@ vlmul_for_first_sew_second_ratio (const vector_insn_info
&info1,
return calculate_vlmul (info1.get_sew (), info2.get_ratio ());
}
+static vlmul_type
+vlmul_for_greatest_sew_second_ratio (const vector_insn_info &info1,
+ const vector_insn_info &info2)
+{
+ return calculate_vlmul (MAX (info1.get_sew (), info2.get_sew ()),
+ info2.get_ratio ());
+}
+
static unsigned
ratio_for_second_sew_first_vlmul (const vector_insn_info &info1,
const vector_insn_info &info2)
diff --git a/gcc/config/riscv/riscv-vsetvl.def
b/gcc/config/riscv/riscv-vsetvl.def
index 7289c01efcf..709cc4ee0df 100644
--- a/gcc/config/riscv/riscv-vsetvl.def
+++ b/gcc/config/riscv/riscv-vsetvl.def
@@ -329,8 +329,8 @@ DEF_SEW_LMUL_FUSE_RULE (/*SEW*/ DEMAND_TRUE, /*LMUL*/
DEMAND_FALSE,
/*NEW_DEMAND_SEW*/ true,
/*NEW_DEMAND_LMUL*/ false,
/*NEW_DEMAND_RATIO*/ true,
- /*NEW_DEMAND_GE_SEW*/ true, greatest_sew, first_vlmul,
- second_ratio)
+ /*NEW_DEMAND_GE_SEW*/ true, greatest_sew,
+ vlmul_for_greatest_sew_second_ratio, second_ratio)
DEF_SEW_LMUL_FUSE_RULE (/*SEW*/ DEMAND_TRUE, /*LMUL*/ DEMAND_FALSE,
/*RATIO*/ DEMAND_ANY, /*GE_SEW*/ DEMAND_TRUE,
/*SEW*/ DEMAND_FALSE, /*LMUL*/ DEMAND_TRUE,
--
2.36.3
