The backend pattern for storing a pair of identical values in 32 and
64-bit modes with the machine instruction STP was missing, and
multiple instructions were needed to reproduce this behavior as a
result of failed RTL pattern match in the combine pass.
For the test case:
typedef long long v2di __attribute__((vector_size (16)));
typedef int v2si __attribute__((vector_size (8)));
void
foo (v2di *x, long long a)
{
v2di tmp = {a, a};
*x = tmp;
}
void
foo2 (v2si *x, int a)
{
v2si tmp = {a, a};
*x = tmp;
}
at -O2 on aarch64 gives:
foo
stp x1, x1, [x0]
ret
foo2:
stp w1, w1, [x0]
ret
instead of:
foo:
dup v0.2d, x1
str q0, [x0]
ret
foo2:
dup v0.2s, w1
str d0, [x0]
ret
Bootstrapped and regtested on aarch64-none-linux-gnu. Ok to install?
gcc/
* config/aarch64/aarch64-simd.md(aarch64_simd_stp<mode>): New.
* config/aarch64/constraints.md: Make "Umn" relaxed memory
constraint.
* config/aarch64/iterators.md(ldpstp_vel_sz): New.
gcc/testsuite/
* gcc.target/aarch64/stp_vec_dup_32_64-1.c:
---
gcc/config/aarch64/aarch64-simd.md | 10 ++++
gcc/config/aarch64/constraints.md | 2 +-
gcc/config/aarch64/iterators.md | 3 +
.../gcc.target/aarch64/stp_vec_dup_32_64-1.c | 57 +++++++++++++++++++
4 files changed, 71 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gcc.target/aarch64/stp_vec_dup_32_64-1.c
diff --git a/gcc/config/aarch64/aarch64-simd.md
b/gcc/config/aarch64/aarch64-simd.md
index de2b7383749..8b5e67bd100 100644
--- a/gcc/config/aarch64/aarch64-simd.md
+++ b/gcc/config/aarch64/aarch64-simd.md
@@ -229,6 +229,16 @@
[(set_attr "type" "neon_stp")]
)
+(define_insn "aarch64_simd_stp<mode>"
+ [(set (match_operand:VP_2E 0 "aarch64_mem_pair_lanes_operand" "=Umn,Umn")
+ (vec_duplicate:VP_2E (match_operand:<VEL> 1 "register_operand" "w,r")))]
+ "TARGET_SIMD"
+ "@
+ stp\\t%<Vetype>1, %<Vetype>1, %y0
+ stp\\t%<vw>1, %<vw>1, %y0"
+ [(set_attr "type" "neon_stp, store_<ldpstp_vel_sz>")]
+)
+
(define_insn "load_pair<VQ:mode><VQ2:mode>"
[(set (match_operand:VQ 0 "register_operand" "=w")
(match_operand:VQ 1 "aarch64_mem_pair_operand" "Ump"))
diff --git a/gcc/config/aarch64/constraints.md
b/gcc/config/aarch64/constraints.md
index 5b20abc27e5..6df1dbec2a8 100644
--- a/gcc/config/aarch64/constraints.md
+++ b/gcc/config/aarch64/constraints.md
@@ -287,7 +287,7 @@
;; Used for storing or loading pairs in an AdvSIMD register using an STP/LDP
;; as a vector-concat. The address mode uses the same constraints as if it
;; were for a single value.
-(define_memory_constraint "Umn"
+(define_relaxed_memory_constraint "Umn"
"@internal
A memory address suitable for a load/store pair operation."
(and (match_code "mem")
diff --git a/gcc/config/aarch64/iterators.md b/gcc/config/aarch64/iterators.md
index 6cbc97cc82c..980dacb8025 100644
--- a/gcc/config/aarch64/iterators.md
+++ b/gcc/config/aarch64/iterators.md
@@ -1017,6 +1017,9 @@
;; Likewise for load/store pair.
(define_mode_attr ldpstp_sz [(SI "8") (DI "16")])
+;; Size of element access for STP/LDP-generated vectors.
+(define_mode_attr ldpstp_vel_sz [(V2SI "8") (V2SF "8") (V2DI "16") (V2DF
"16")])
+
;; For inequal width int to float conversion
(define_mode_attr w1 [(HF "w") (SF "w") (DF "x")])
(define_mode_attr w2 [(HF "x") (SF "x") (DF "w")])
diff --git a/gcc/testsuite/gcc.target/aarch64/stp_vec_dup_32_64-1.c
b/gcc/testsuite/gcc.target/aarch64/stp_vec_dup_32_64-1.c
new file mode 100644
index 00000000000..fc2c1ea39e0
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/stp_vec_dup_32_64-1.c
@@ -0,0 +1,57 @@
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+
+typedef long long v2di __attribute__((vector_size (16)));
+typedef int v2si __attribute__((vector_size (8)));
+
+#define TESTV2DI(lab, idx) \
+ void \
+ stpv2di_##lab (v2di *x, long long a) \
+ { \
+ v2di tmp = {a, a}; \
+ x[idx] = tmp; \
+ }
+
+
+#define TESTV2SI(lab, idx) \
+ void \
+ stpv2si_##lab (v2si *x, int a) \
+ { \
+ v2si tmp = {a, a}; \
+ x[idx] = tmp; \
+ } \
+
+/* Core test, no imm assembler offset: */
+
+TESTV2SI(0, 0)
+TESTV2DI(0, 0)
+/* { dg-final { scan-assembler {\s+stp\t(w[0-9]+), \1, \[x[0-9]+\]} } } */
+/* { dg-final { scan-assembler {\s+stp\t(x[0-9]+), \1, \[x[0-9]+\]} } } */
+
+/* Lower offset bounds: */
+
+/* Vaid offsets: */
+TESTV2SI(1, -32)
+TESTV2DI(1, -32)
+/* { dg-final { scan-assembler {\s+stp\t(w[0-9]+), \1, \[x[0-9]+, -256\]} } }
*/
+/* { dg-final { scan-assembler {\s+stp\t(x[0-9]+), \1, \[x[0-9]+, -512\]} } }
*/
+/* Invalid offsets: */
+TESTV2SI(2, -33)
+TESTV2DI(2, -33)
+/* { dg-final { scan-assembler-not {\s+stp\t(w[0-9]+), \1, \[x[0-9]+, -264\]}
} } */
+/* { dg-final { scan-assembler-not {\s+stp\t(x[0-9]+), \1, \[x[0-9]+, -528\]}
} } */
+
+/* Upper offset bounds: */
+
+/* Valid offsets: */
+TESTV2SI(3, 31)
+TESTV2DI(3, 31)
+/* { dg-final { scan-assembler {\s+stp\t(w[0-9]+), \1, \[x[0-9]+, 248\]} } } */
+/* { dg-final { scan-assembler {\s+stp\t(x[0-9]+), \1, \[x[0-9]+, 496\]} } } */
+/* Invalid offsets: */
+TESTV2SI(4, 32)
+TESTV2DI(4, 32)
+/* { dg-final { scan-assembler-not {\s+stp\t(w[0-9]+), \1, \[x[0-9]+, 256\]} }
} */
+/* { dg-final { scan-assembler-not {\s+stp\t(x[0-9]+), \1, \[x[0-9]+, 512\]} }
} */
+
+
--
2.25.1
