This patch fixes a bug of VSETVL PASS in this following situation:
Ignore curr info since prev info available with it:
prev_info: VALID (insn 8, bb 2)
Demand fields: demand_ratio_and_ge_sew demand_avl
SEW=16, VLMUL=mf4, RATIO=64, MAX_SEW=64
TAIL_POLICY=agnostic, MASK_POLICY=agnostic
AVL=(const_int 1 [0x1])
VL=(nil)
curr_info: VALID (insn 12, bb 2)
Demand fields: demand_ge_sew demand_non_zero_avl
SEW=16, VLMUL=m1, RATIO=16, MAX_SEW=32
TAIL_POLICY=agnostic, MASK_POLICY=agnostic
AVL=(const_int 1 [0x1])
VL=(nil)
We should update prev_info MAX_SEW from 64 into 32.
Before this patch:
foo:
vsetivli zero,1,e64,m1,ta,ma
vle64.v v1,0(a1)
vmv.s.x v3,a0
vfmv.s.f v2,fa0
vadd.vv v1,v1,v1
ret
After this patch:
foo:
vsetivli zero,1,e16,mf4,ta,ma
vle64.v v1,0(a1)
vmv.s.x v3,a0
vfmv.s.f v2,fa0
vsetvli zero,zero,e64,m1,ta,ma
vadd.vv v1,v1,v1
ret
Tested on both RV32 and RV64 no regression. Committed.
PR target/113248
gcc/ChangeLog:
* config/riscv/riscv-vsetvl.cc (pre_vsetvl::fuse_local_vsetvl_info):
gcc/testsuite/ChangeLog:
* gcc.target/riscv/rvv/vsetvl/pr113248.c: New test.
---
gcc/config/riscv/riscv-vsetvl.cc | 17 +++++++++++++++++
.../gcc.target/riscv/rvv/vsetvl/pr113248.c | 15 +++++++++++++++
2 files changed, 32 insertions(+)
create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/vsetvl/pr113248.c
diff --git a/gcc/config/riscv/riscv-vsetvl.cc b/gcc/config/riscv/riscv-vsetvl.cc
index 3a2ea9ad44a..7d748edc0ef 100644
--- a/gcc/config/riscv/riscv-vsetvl.cc
+++ b/gcc/config/riscv/riscv-vsetvl.cc
@@ -2876,6 +2876,23 @@ pre_vsetvl::fuse_local_vsetvl_info ()
curr_info.dump (dump_file, " ");
fprintf (dump_file, "\n");
}
+ /* Even though prev_info is available with curr_info,
+ we need to update the MAX_SEW of prev_info since
+ we don't check MAX_SEW in available_p check.
+
+ prev_info:
+ Demand fields: demand_ratio_and_ge_sew demand_avl
+ SEW=16, VLMUL=mf4, RATIO=64, MAX_SEW=64
+
+ curr_info:
+ Demand fields: demand_ge_sew demand_non_zero_avl
+ SEW=16, VLMUL=m1, RATIO=16, MAX_SEW=32
+
+ In the example above, prev_info is available with
+ curr_info, we need to update prev_info MAX_SEW from
+ 64 into 32. */
+ prev_info.set_max_sew (
+ MIN (prev_info.get_max_sew (), curr_info.get_max_sew ()));
if (!curr_info.vl_used_by_non_rvv_insn_p ()
&& vsetvl_insn_p (curr_info.get_insn ()->rtl ()))
m_delete_list.safe_push (curr_info);
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/vsetvl/pr113248.c
b/gcc/testsuite/gcc.target/riscv/rvv/vsetvl/pr113248.c
new file mode 100644
index 00000000000..b3b506177df
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/vsetvl/pr113248.c
@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+/* { dg-options "-mtune=generic-ooo --param=riscv-autovec-preference=scalable
-march=rv32gc_zve64f_zvfh -mabi=ilp32d -O3" } */
+
+#include "riscv_vector.h"
+
+void foo(_Float16 y, int64_t *i64p)
+{
+ vint64m1_t vx =__riscv_vle64_v_i64m1 (i64p, 1);
+ vx = __riscv_vadd_vv_i64m1 (vx, vx, 1);
+ vfloat16m1_t vy =__riscv_vfmv_s_f_f16m1 (y, 1);
+ asm volatile ("# use %0 %1" : : "vr"(vx), "vr" (vy));
+}
+
+/* { dg-final { scan-assembler-times
{vsetivli\s+zero,\s*1,\s*e16,\s*mf4,\s*t[au],\s*m[au]} 1 } } */
+/* { dg-final { scan-assembler-times
{vsetvli\s+zero,\s*zero,\s*e64,\s*m1,\s*t[au],\s*m[au]} 1 } } */
--
2.36.3
