DSE: Allow vector type for get_stored_val when read < store

Update in v4:
* Merge upstream and removed some independent changes.

Update in v3:
* Take known_le instead of known_lt for vector size.
* Return NULL_RTX when gap is not equal 0 and not constant.

Update in v2:
* Move vector type support to get_stored_val.

Original log:

This patch would like to allow the vector mode in the
get_stored_val in the DSE. It is valid for the read
rtx if and only if the read bitsize is less than the
stored bitsize.

Given below example code with
--param=riscv-autovec-preference=fixed-vlmax.

vuint8m1_t test () {
  uint8_t arr[32] = {
    1, 2, 7, 1, 3, 4, 5, 3, 1, 0, 1, 2, 4, 4, 9, 9,
    1, 2, 7, 1, 3, 4, 5, 3, 1, 0, 1, 2, 4, 4, 9, 9,
  };

  return __riscv_vle8_v_u8m1(arr, 32);
}

Before this patch:
test:
  lui     a5,%hi(.LANCHOR0)
  addi    sp,sp,-32
  addi    a5,a5,%lo(.LANCHOR0)
  li      a3,32
  vl2re64.v       v2,0(a5)
  vsetvli zero,a3,e8,m1,ta,ma
  vs2r.v  v2,0(sp)             <== Unnecessary store to stack
  vle8.v  v1,0(sp)             <== Ditto
  vs1r.v  v1,0(a0)
  addi    sp,sp,32
  jr      ra

After this patch:
test:
  lui     a5,%hi(.LANCHOR0)
  addi    a5,a5,%lo(.LANCHOR0)
  li      a4,32
  addi    sp,sp,-32
  vsetvli zero,a4,e8,m1,ta,ma
  vle8.v  v1,0(a5)
  vs1r.v  v1,0(a0)
  addi    sp,sp,32
  jr      ra

Below tests are passed within this patch:
* The risc-v regression test.
* The x86 bootstrap and regression test.
* The aarch64 regression test.

	PR target/111720

gcc/ChangeLog:

	* dse.cc (get_stored_val): Allow vector mode if read size is
	less than or equal to stored size.

gcc/testsuite/ChangeLog:

	* gcc.target/riscv/rvv/base/pr111720-0.c: New test.
	* gcc.target/riscv/rvv/base/pr111720-1.c: New test.
	* gcc.target/riscv/rvv/base/pr111720-10.c: New test.
	* gcc.target/riscv/rvv/base/pr111720-2.c: New test.
	* gcc.target/riscv/rvv/base/pr111720-3.c: New test.
	* gcc.target/riscv/rvv/base/pr111720-4.c: New test.
	* gcc.target/riscv/rvv/base/pr111720-5.c: New test.
	* gcc.target/riscv/rvv/base/pr111720-6.c: New test.
	* gcc.target/riscv/rvv/base/pr111720-7.c: New test.
	* gcc.target/riscv/rvv/base/pr111720-8.c: New test.
	* gcc.target/riscv/rvv/base/pr111720-9.c: New test.

Signed-off-by: Pan Li <pan2.li@intel.com>

gcc/dse.cc

@@ -1900,8 +1900,11 @@ get_stored_val (store_info *store_info, machine_mode read_mode,
   else
     gap = read_offset - store_info->offset;
 
-  if (gap.is_constant () && maybe_ne (gap, 0))
+  if (maybe_ne (gap, 0))
     {
+      if (!gap.is_constant ())
+	return NULL_RTX;
+
       poly_int64 shift = gap * BITS_PER_UNIT;
       poly_int64 access_size = GET_MODE_SIZE (read_mode) + gap;
       read_reg = find_shift_sequence (access_size, store_info, read_mode,
@@ -1940,6 +1943,10 @@ get_stored_val (store_info *store_info, machine_mode read_mode,
 	       || GET_MODE_CLASS (read_mode) != GET_MODE_CLASS (store_mode)))
     read_reg = extract_low_bits (read_mode, store_mode,
 				 copy_rtx (store_info->const_rhs));
+  else if (VECTOR_MODE_P (read_mode) && VECTOR_MODE_P (store_mode)
+    && known_le (GET_MODE_BITSIZE (read_mode), GET_MODE_BITSIZE (store_mode))
+    && targetm.modes_tieable_p (read_mode, store_mode))
+    read_reg = gen_lowpart (read_mode, copy_rtx (store_info->rhs));
   else
     read_reg = extract_low_bits (read_mode, store_mode,
 				 copy_rtx (store_info->rhs));

gcc/testsuite/gcc.target/riscv/rvv/base/pr111720-0.c

@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -march=rv64gcv -mabi=lp64d -ftree-vectorize --param=riscv-autovec-preference=fixed-vlmax -Wno-psabi" } */
+
+#include "riscv_vector.h"
+
+vuint8m1_t test () {
+  uint8_t arr[32] = {
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+  };
+
+  return __riscv_vle8_v_u8m1(arr, 32);
+}
+
+/* { dg-final { scan-assembler-not {vle[0-9]+\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */
+/* { dg-final { scan-assembler-not {vs[0-9]+r\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */

gcc/testsuite/gcc.target/riscv/rvv/base/pr111720-1.c

@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -march=rv64gcv -mabi=lp64d -ftree-vectorize --param=riscv-autovec-preference=fixed-vlmax -Wno-psabi" } */
+
+#include "riscv_vector.h"
+
+vuint8m2_t test () {
+  uint8_t arr[32] = {
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+  };
+
+  return __riscv_vle8_v_u8m2(arr, 32);
+}
+
+/* { dg-final { scan-assembler-not {vle[0-9]+\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */
+/* { dg-final { scan-assembler-not {vs[09]+r\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */

gcc/testsuite/gcc.target/riscv/rvv/base/pr111720-10.c

@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -march=rv64gcv -mabi=lp64d -ftree-vectorize --param=riscv-autovec-preference=fixed-vlmax -Wno-psabi" } */
+
+#include "riscv_vector.h"
+
+vbool4_t test () {
+  uint8_t arr[32] = {
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+  };
+
+  return __riscv_vlm_v_b4(arr, 32);
+}
+
+/* { dg-final { scan-assembler-not {vle[0-9]+\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */
+/* { dg-final { scan-assembler-not {vs[0-9]+r\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */

gcc/testsuite/gcc.target/riscv/rvv/base/pr111720-2.c

@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -march=rv64gcv -mabi=lp64d -ftree-vectorize --param=riscv-autovec-preference=fixed-vlmax -Wno-psabi" } */
+
+#include "riscv_vector.h"
+
+vuint8m1_t test () {
+  uint8_t arr[32] = {
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+  };
+
+  return __riscv_vle8_v_u8m1(arr, 16);
+}
+
+/* { dg-final { scan-assembler-not {vle[0-9]+\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */
+/* { dg-final { scan-assembler-not {vs[0-9]+r\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */

gcc/testsuite/gcc.target/riscv/rvv/base/pr111720-3.c

@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -march=rv64gcv -mabi=lp64d -ftree-vectorize --param=riscv-autovec-preference=fixed-vlmax -Wno-psabi" } */
+
+#include "riscv_vector.h"
+
+vuint8m2_t test () {
+  uint8_t arr[32] = {
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+  };
+
+  return __riscv_vle8_v_u8m2(arr, 8);
+}
+
+/* { dg-final { scan-assembler-not {vle[0-9]+\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */
+/* { dg-final { scan-assembler-not {vs[09]+r\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */

gcc/testsuite/gcc.target/riscv/rvv/base/pr111720-4.c

@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -march=rv64gcv -mabi=lp64d -ftree-vectorize --param=riscv-autovec-preference=fixed-vlmax -Wno-psabi" } */
+
+#include "riscv_vector.h"
+
+vuint8mf2_t test () {
+  uint8_t arr[32] = {
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+  };
+
+  return __riscv_vle8_v_u8mf2(arr, 32);
+}
+
+/* { dg-final { scan-assembler-not {vle[0-9]+\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */
+/* { dg-final { scan-assembler-not {vs[0-9]+r\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */

gcc/testsuite/gcc.target/riscv/rvv/base/pr111720-5.c

@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -march=rv64gcv -mabi=lp64d -ftree-vectorize --param=riscv-autovec-preference=fixed-vlmax -Wno-psabi" } */
+
+#include "riscv_vector.h"
+
+vuint8m2_t test () {
+  uint8_t arr[32] = {
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+  };
+
+  return __riscv_vle8_v_u8m2(arr, 4);
+}
+
+/* { dg-final { scan-assembler-not {vle[0-9]+\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */
+/* { dg-final { scan-assembler-not {vs[09]+r\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */

gcc/testsuite/gcc.target/riscv/rvv/base/pr111720-6.c

@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -march=rv64gcv -mabi=lp64d -ftree-vectorize --param=riscv-autovec-preference=fixed-vlmax -Wno-psabi" } */
+
+#include "riscv_vector.h"
+
+vuint8m8_t test () {
+  uint8_t arr[32] = {
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+  };
+
+  return __riscv_vle8_v_u8m8(arr, 32);
+}
+
+/* { dg-final { scan-assembler-times {vle[0-9]+\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} 1 } } */
+/* { dg-final { scan-assembler-times {vs[0-9]+r\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} 1 } } */

gcc/testsuite/gcc.target/riscv/rvv/base/pr111720-7.c

@@ -0,0 +1,21 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -march=rv64gcv -mabi=lp64d -ftree-vectorize --param=riscv-autovec-preference=fixed-vlmax -Wno-psabi" } */
+
+#include "riscv_vector.h"
+
+vbool8_t test () {
+  uint8_t arr[32] = {
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+    1, 2, 7, 1, 3, 4, 5, 3,
+    1, 0, 1, 2, 4, 4, 9, 9,
+  };
+
+  vuint8m1_t varr = __riscv_vle8_v_u8m1(arr, 32);
+  vuint8m1_t vand_m = __riscv_vand_vx_u8m1(varr, 1, 32);
+
+  return __riscv_vreinterpret_v_u8m1_b8(vand_m);
+}
+
+/* { dg-final { scan-assembler-not {vle[0-9]+\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */
+/* { dg-final { scan-assembler-not {vs[0-9]+r\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */

gcc/testsuite/gcc.target/riscv/rvv/base/pr111720-8.c

@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -march=rv64gcv -mabi=lp64d -ftree-vectorize --param=riscv-autovec-preference=fixed-vlmax -Wno-psabi" } */
+
+#include "riscv_vector.h"
+
+vfloat32m1_t test () {
+  float arr[32] = {
+    1.0, 2.2, 7.8, 1.2, 3.3, 4.7, 5.5, 3.3,
+    1.0, 0.2, 1.8, 2.2, 4.3, 4.7, 9.5, 9.3,
+    1.0, 2.2, 7.8, 1.2, 3.3, 4.7, 5.5, 3.3,
+    1.0, 0.2, 1.8, 2.2, 4.3, 4.7, 9.5, 9.3,
+  };
+
+  return __riscv_vle32_v_f32m1(arr, 32);
+}
+
+/* { dg-final { scan-assembler-not {vle[0-9]+\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */
+/* { dg-final { scan-assembler-not {vs[0-9]+r\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} } } */

gcc/testsuite/gcc.target/riscv/rvv/base/pr111720-9.c

@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -march=rv64gcv -mabi=lp64d -ftree-vectorize --param=riscv-autovec-preference=fixed-vlmax -Wno-psabi" } */
+
+#include "riscv_vector.h"
+
+vfloat64m8_t test () {
+  double arr[8] = {
+    1.0, 2.2, 7.8, 1.2, 3.3, 4.7, 5.5, 3.3,
+  };
+
+  return __riscv_vle64_v_f64m8(arr, 4);
+}
+
+/* { dg-final { scan-assembler-times {vle[0-9]+\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} 1 } } */
+/* { dg-final { scan-assembler-times {vs[0-9]+r\.v\s+v[0-9]+,\s*[0-9]+\(sp\)} 1 } } */