From: Juzhe-Zhong <juzhe.zhong@rivai.ai>
To: gcc-patches@gcc.gnu.org
Cc: kito.cheng@gmail.com, kito.cheng@sifive.com, palmer@dabbelt.com,
palmer@rivosinc.com, jeffreyalaw@gmail.com, rdapp.gcc@gmail.com,
Juzhe-Zhong <juzhe.zhong@rivai.ai>
Subject: [PATCH V2] RISC-V: Fix bug of pre-calculated const vector mask
Date: Wed, 28 Jun 2023 09:59:44 +0800 [thread overview]
Message-ID: <20230628015944.112659-1-juzhe.zhong@rivai.ai> (raw)
This bug blocks the following patches.
GCC doesn't know RVV is using compact mask model.
Consider this following case:
#define N 16
int
main ()
{
int8_t mask[N] = {0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1};
int8_t out[N] = {0};
for (int8_t i = 0; i < N; ++i)
if (mask[i])
out[i] = i;
for (int8_t i = 0; i < N; ++i)
{
if (mask[i])
assert (out[i] == i);
else
assert (out[i] == 0);
}
}
Before this patch, the pre-calculated mask in constant memory pool:
.LC1:
.byte 68 ====> 0b01000100
This is incorrect, such case failed in execution.
After this patch:
.LC1:
.byte 10 ====> 0b1010
Pass on exection.
gcc/ChangeLog:
* config/riscv/riscv-v.cc (rvv_builder::get_compact_mask): New function.
(expand_const_vector): Ditto.
* config/riscv/riscv.cc (riscv_const_insns): Ditto.
gcc/testsuite/ChangeLog:
* gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-1.c: New test.
* gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-2.c: New test.
* gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-3.c: New test.
* gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-4.c: New test.
* gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-5.c: New test.
* gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-6.c: New test.
* gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-7.c: New test.
* gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-8.c: New test.
* gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-9.c: New test.
---
gcc/config/riscv/riscv-v.cc | 64 +++++++++++++++++--
gcc/config/riscv/riscv.cc | 6 ++
.../riscv/rvv/autovec/vls-vlmax/bitmask-1.c | 23 +++++++
.../riscv/rvv/autovec/vls-vlmax/bitmask-2.c | 23 +++++++
.../riscv/rvv/autovec/vls-vlmax/bitmask-3.c | 23 +++++++
.../riscv/rvv/autovec/vls-vlmax/bitmask-4.c | 23 +++++++
.../riscv/rvv/autovec/vls-vlmax/bitmask-5.c | 25 ++++++++
.../riscv/rvv/autovec/vls-vlmax/bitmask-6.c | 27 ++++++++
.../riscv/rvv/autovec/vls-vlmax/bitmask-7.c | 30 +++++++++
.../riscv/rvv/autovec/vls-vlmax/bitmask-8.c | 30 +++++++++
.../riscv/rvv/autovec/vls-vlmax/bitmask-9.c | 30 +++++++++
11 files changed, 299 insertions(+), 5 deletions(-)
create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-1.c
create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-2.c
create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-3.c
create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-4.c
create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-5.c
create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-6.c
create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-7.c
create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-8.c
create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-9.c
diff --git a/gcc/config/riscv/riscv-v.cc b/gcc/config/riscv/riscv-v.cc
index adb8d7d36a5..5da0dc5e998 100644
--- a/gcc/config/riscv/riscv-v.cc
+++ b/gcc/config/riscv/riscv-v.cc
@@ -291,6 +291,7 @@ public:
bool single_step_npatterns_p () const;
bool npatterns_all_equal_p () const;
+ rtx get_compact_mask () const;
machine_mode new_mode () const { return m_new_mode; }
scalar_mode inner_mode () const { return m_inner_mode; }
@@ -505,6 +506,47 @@ rvv_builder::npatterns_all_equal_p () const
return true;
}
+/* Generate the compact mask.
+
+ E.g: mask = { 0, -1 }, mode = VNx2BI, bitsize = 128bits.
+
+ GCC by default will generate the mask = 0b00000001xxxxx.
+
+ However, it's not expected mask for RVV since RVV
+ prefers the compact mask = 0b10xxxxx.
+*/
+rtx
+rvv_builder::get_compact_mask () const
+{
+ /* If TARGET_MIN_VLEN == 32, the minimum LMUL = 1/4.
+ Otherwise, the minimum LMUL = 1/8. */
+ unsigned min_lmul = TARGET_MIN_VLEN == 32 ? 4 : 8;
+ unsigned min_container_size
+ = BYTES_PER_RISCV_VECTOR.to_constant () / min_lmul;
+ unsigned container_size = MAX (CEIL (npatterns (), 8), min_container_size);
+ machine_mode container_mode
+ = get_vector_mode (QImode, container_size).require ();
+
+ unsigned nunits = GET_MODE_NUNITS (container_mode).to_constant ();
+ rtvec v = rtvec_alloc (nunits);
+ for (unsigned i = 0; i < nunits; i++)
+ RTVEC_ELT (v, i) = const0_rtx;
+
+ unsigned char b = 0;
+ for (unsigned i = 0; i < npatterns (); i++)
+ {
+ if (INTVAL (elt (i)))
+ b = b | (1 << (i % 8));
+
+ if ((i > 0 && (i % 8) == 7) || (i == (npatterns () - 1)))
+ {
+ RTVEC_ELT (v, ((i + 7) / 8) - 1) = gen_int_mode (b, QImode);
+ b = 0;
+ }
+ }
+ return gen_rtx_CONST_VECTOR (container_mode, v);
+}
+
static unsigned
get_sew (machine_mode mode)
{
@@ -1141,11 +1183,23 @@ expand_const_vector (rtx target, rtx src)
if (GET_MODE_CLASS (mode) == MODE_VECTOR_BOOL)
{
rtx elt;
- gcc_assert (
- const_vec_duplicate_p (src, &elt)
- && (rtx_equal_p (elt, const0_rtx) || rtx_equal_p (elt, const1_rtx)));
- rtx ops[] = {target, src};
- emit_vlmax_insn (code_for_pred_mov (mode), RVV_UNOP, ops);
+ unsigned int nelts;
+ if (const_vec_duplicate_p (src, &elt))
+ {
+ rtx ops[] = {target, src};
+ emit_vlmax_insn (code_for_pred_mov (mode), RVV_UNOP, ops);
+ }
+ else if (GET_MODE_NUNITS (mode).is_constant (&nelts))
+ {
+ rvv_builder builder (mode, nelts, 1);
+ for (unsigned int i = 0; i < nelts; i++)
+ builder.quick_push (CONST_VECTOR_ELT (src, i));
+ rtx mask = builder.get_compact_mask ();
+ rtx mem = validize_mem (force_const_mem (GET_MODE (mask), mask));
+ emit_move_insn (target, gen_rtx_MEM (mode, XEXP (mem, 0)));
+ }
+ else
+ gcc_unreachable ();
return;
}
diff --git a/gcc/config/riscv/riscv.cc b/gcc/config/riscv/riscv.cc
index 280aa0b33b9..86c83f0906d 100644
--- a/gcc/config/riscv/riscv.cc
+++ b/gcc/config/riscv/riscv.cc
@@ -1323,6 +1323,12 @@ riscv_const_insns (rtx x)
return 1 + 4; /*vmv.v.x + memory access. */
}
}
+
+ /* GCC doesn't known RVV is using compact model of mask,
+ we should by default handle mask in mov<mode> pattern. */
+ if (GET_MODE_CLASS (GET_MODE (x)) == MODE_VECTOR_BOOL)
+ /* TODO: We can adjust it according real cost model of vlm.v. */
+ return 1;
}
/* TODO: We may support more const vector in the future. */
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-1.c b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-1.c
new file mode 100644
index 00000000000..81229fd62b9
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-1.c
@@ -0,0 +1,23 @@
+/* { dg-do run { target { riscv_vector } } } */
+/* { dg-options "--param riscv-autovec-preference=fixed-vlmax -O3" } */
+
+#include <stdint-gcc.h>
+#include <assert.h>
+#define N 16
+
+int
+main ()
+{
+ int mask[N] = {0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1};
+ int64_t out[N] = {0};
+ for (int i = 0; i < N; ++i)
+ if (mask[i])
+ out[i] = i;
+ for (int i = 0; i < N; ++i)
+ {
+ if (mask[i])
+ assert (out[i] == i);
+ else
+ assert (out[i] == 0);
+ }
+}
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-2.c b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-2.c
new file mode 100644
index 00000000000..a23e47171bc
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-2.c
@@ -0,0 +1,23 @@
+/* { dg-do run { target { riscv_vector } } } */
+/* { dg-options "--param riscv-autovec-preference=fixed-vlmax -O3" } */
+
+#include <stdint-gcc.h>
+#include <assert.h>
+#define N 16
+
+int
+main ()
+{
+ int mask[N] = {0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1};
+ int out[N] = {0};
+ for (int i = 0; i < N; ++i)
+ if (mask[i])
+ out[i] = i;
+ for (int i = 0; i < N; ++i)
+ {
+ if (mask[i])
+ assert (out[i] == i);
+ else
+ assert (out[i] == 0);
+ }
+}
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-3.c b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-3.c
new file mode 100644
index 00000000000..6ea8fdd89c0
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-3.c
@@ -0,0 +1,23 @@
+/* { dg-do run { target { riscv_vector } } } */
+/* { dg-options "--param riscv-autovec-preference=fixed-vlmax -O3" } */
+
+#include <stdint-gcc.h>
+#include <assert.h>
+#define N 16
+
+int
+main ()
+{
+ int16_t mask[N] = {0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1};
+ int16_t out[N] = {0};
+ for (int16_t i = 0; i < N; ++i)
+ if (mask[i])
+ out[i] = i;
+ for (int16_t i = 0; i < N; ++i)
+ {
+ if (mask[i])
+ assert (out[i] == i);
+ else
+ assert (out[i] == 0);
+ }
+}
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-4.c b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-4.c
new file mode 100644
index 00000000000..2d97c26abfd
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-4.c
@@ -0,0 +1,23 @@
+/* { dg-do run { target { riscv_vector } } } */
+/* { dg-options "--param riscv-autovec-preference=fixed-vlmax -O3" } */
+
+#include <stdint-gcc.h>
+#include <assert.h>
+#define N 16
+
+int
+main ()
+{
+ int8_t mask[N] = {0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1};
+ int8_t out[N] = {0};
+ for (int8_t i = 0; i < N; ++i)
+ if (mask[i])
+ out[i] = i;
+ for (int8_t i = 0; i < N; ++i)
+ {
+ if (mask[i])
+ assert (out[i] == i);
+ else
+ assert (out[i] == 0);
+ }
+}
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-5.c b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-5.c
new file mode 100644
index 00000000000..b89b70e99a6
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-5.c
@@ -0,0 +1,25 @@
+/* { dg-do run { target { riscv_vector } } } */
+/* { dg-options "--param riscv-autovec-preference=fixed-vlmax --param riscv-autovec-lmul=m2 -O3" } */
+
+#include <stdint-gcc.h>
+#include <assert.h>
+
+#define N 32
+
+int
+main ()
+{
+ int8_t mask[N] = {0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1};
+ int8_t out[N] = {0};
+ for (int8_t i = 0; i < N; ++i)
+ if (mask[i])
+ out[i] = i;
+ for (int8_t i = 0; i < N; ++i)
+ {
+ if (mask[i])
+ assert (out[i] == i);
+ else
+ assert (out[i] == 0);
+ }
+}
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-6.c b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-6.c
new file mode 100644
index 00000000000..ac8d91e793b
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-6.c
@@ -0,0 +1,27 @@
+/* { dg-do run { target { riscv_vector } } } */
+/* { dg-options "--param riscv-autovec-preference=fixed-vlmax --param riscv-autovec-lmul=m4 -O3" } */
+
+#include <stdint-gcc.h>
+#include <assert.h>
+
+#define N 64
+
+int
+main ()
+{
+ int8_t mask[N] = {0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1};
+ int8_t out[N] = {0};
+ for (int8_t i = 0; i < N; ++i)
+ if (mask[i])
+ out[i] = i;
+ for (int8_t i = 0; i < N; ++i)
+ {
+ if (mask[i])
+ assert (out[i] == i);
+ else
+ assert (out[i] == 0);
+ }
+}
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-7.c b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-7.c
new file mode 100644
index 00000000000..f538db23b1d
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-7.c
@@ -0,0 +1,30 @@
+/* { dg-do run { target { riscv_vector } } } */
+/* { dg-options "--param riscv-autovec-preference=fixed-vlmax --param riscv-autovec-lmul=m8 -O3" } */
+
+#include <stdint-gcc.h>
+#include <assert.h>
+
+#define N 128
+
+int
+main ()
+{
+ uint8_t mask[N]
+ = {0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1};
+ uint8_t out[N] = {0};
+ for (uint8_t i = 0; i < N; ++i)
+ if (mask[i])
+ out[i] = i;
+ for (uint8_t i = 0; i < N; ++i)
+ {
+ if (mask[i])
+ assert (out[i] == i);
+ else
+ assert (out[i] == 0);
+ }
+}
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-8.c b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-8.c
new file mode 100644
index 00000000000..5abb34c1686
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-8.c
@@ -0,0 +1,30 @@
+/* { dg-do run { target { riscv_vector } } } */
+/* { dg-options "--param riscv-autovec-preference=fixed-vlmax --param riscv-autovec-lmul=m8 -O3" } */
+
+#include <stdint-gcc.h>
+#include <assert.h>
+
+#define N 128
+
+int
+main ()
+{
+ int mask[N]
+ = {0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1};
+ int out[N] = {0};
+ for (int i = 0; i < N; ++i)
+ if (mask[i])
+ out[i] = i;
+ for (int i = 0; i < N; ++i)
+ {
+ if (mask[i])
+ assert (out[i] == i);
+ else
+ assert (out[i] == 0);
+ }
+}
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-9.c b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-9.c
new file mode 100644
index 00000000000..6fdaa516534
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/bitmask-9.c
@@ -0,0 +1,30 @@
+/* { dg-do run { target { riscv_vector } } } */
+/* { dg-options "--param riscv-autovec-preference=fixed-vlmax --param riscv-autovec-lmul=m8 -O3" } */
+
+#include <stdint-gcc.h>
+#include <assert.h>
+
+#define N 128
+
+int
+main ()
+{
+ int64_t mask[N]
+ = {0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
+ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1};
+ int64_t out[N] = {0};
+ for (int i = 0; i < N; ++i)
+ if (mask[i])
+ out[i] = i;
+ for (int i = 0; i < N; ++i)
+ {
+ if (mask[i])
+ assert (out[i] == i);
+ else
+ assert (out[i] == 0);
+ }
+}
--
2.36.1
next reply other threads:[~2023-06-28 1:59 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-28 1:59 Juzhe-Zhong [this message]
2023-06-28 3:14 ` juzhe.zhong
2023-06-28 3:16 ` Kito Cheng
2023-06-28 3:19 ` juzhe.zhong
2023-06-28 4:09 ` Jeff Law
2023-06-28 6:01 ` Kito Cheng
2023-06-28 6:17 ` juzhe.zhong
2023-06-28 7:17 ` Richard Biener
2023-06-28 7:38 ` juzhe.zhong
2023-06-28 8:15 ` juzhe.zhong
2023-06-28 9:50 ` juzhe.zhong
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