This is an RTL pass that detects store forwarding from stores to larger loads
(load pairs).
This optimization is SPEC2017-driven and was found to be beneficial for some
benchmarks,
through testing on ampere1/ampere1a machines.
For example, it can transform cases like
str d5, [sp, #320]
fmul d5, d31, d29
ldp d31, d17, [sp, #312] # Large load from small store
to
str d5, [sp, #320]
fmul d5, d31, d29
ldr d31, [sp, #312]
ldr d17, [sp, #320]
Currently, the pass is disabled by default on all architectures and enabled by
a target-specific option.
If deemed beneficial enough for a default, it will be enabled on
ampere1/ampere1a,
or other architectures as well, without needing to be turned on by this option.
Bootstrapped and regtested on aarch64-linux.
gcc/ChangeLog:
* config.gcc: Add aarch64-store-forwarding.o to extra_objs.
* config/aarch64/aarch64-passes.def (INSERT_PASS_AFTER): New pass.
* config/aarch64/aarch64-protos.h (make_pass_avoid_store_forwarding):
Declare.
* config/aarch64/aarch64.opt (mavoid-store-forwarding): New option.
(aarch64-store-forwarding-threshold): New param.
* config/aarch64/t-aarch64: Add aarch64-store-forwarding.o
* doc/invoke.texi: Document new option and new param.
* config/aarch64/aarch64-store-forwarding.cc: New file.
gcc/testsuite/ChangeLog:
* gcc.target/aarch64/ldp_ssll_no_overlap_address.c: New test.
* gcc.target/aarch64/ldp_ssll_no_overlap_offset.c: New test.
* gcc.target/aarch64/ldp_ssll_overlap.c: New test.
Signed-off-by: Manos Anagnostakis <manos.anagnosta...@vrull.eu>
Co-Authored-By: Manolis Tsamis <manolis.tsa...@vrull.eu>
Co-Authored-By: Philipp Tomsich <philipp.toms...@vrull.eu>
---
Changes in v2:
- Remove usage of memrefs_conflict_p with the helper
check_memory_reg_ovewrite, which actually prevents some cases of
being handled correctly.
- Code cleanup requested in v1.
gcc/config.gcc | 1 +
gcc/config/aarch64/aarch64-passes.def | 1 +
gcc/config/aarch64/aarch64-protos.h | 1 +
.../aarch64/aarch64-store-forwarding.cc | 323 ++++++++++++++++++
gcc/config/aarch64/aarch64.opt | 9 +
gcc/config/aarch64/t-aarch64 | 10 +
gcc/doc/invoke.texi | 12 +-
.../aarch64/ldp_ssll_no_overlap_address.c | 33 ++
.../aarch64/ldp_ssll_no_overlap_offset.c | 33 ++
.../gcc.target/aarch64/ldp_ssll_overlap.c | 33 ++
10 files changed, 455 insertions(+), 1 deletion(-)
create mode 100644 gcc/config/aarch64/aarch64-store-forwarding.cc
create mode 100644
gcc/testsuite/gcc.target/aarch64/ldp_ssll_no_overlap_address.c
create mode 100644
gcc/testsuite/gcc.target/aarch64/ldp_ssll_no_overlap_offset.c
create mode 100644 gcc/testsuite/gcc.target/aarch64/ldp_ssll_overlap.c
diff --git a/gcc/config.gcc b/gcc/config.gcc
index b88591b6fd8..4eb41584b94 100644
--- a/gcc/config.gcc
+++ b/gcc/config.gcc
@@ -350,6 +350,7 @@ aarch64*-*-*)
cxx_target_objs="aarch64-c.o"
d_target_objs="aarch64-d.o"
extra_objs="aarch64-builtins.o aarch-common.o aarch64-sve-builtins.o
aarch64-sve-builtins-shapes.o aarch64-sve-builtins-base.o
aarch64-sve-builtins-sve2.o cortex-a57-fma-steering.o aarch64-speculation.o
falkor-tag-collision-avoidance.o aarch-bti-insert.o aarch64-cc-fusion.o"
+ extra_objs="${extra_objs} aarch64-store-forwarding.o"
target_gtfiles="\$(srcdir)/config/aarch64/aarch64-builtins.cc
\$(srcdir)/config/aarch64/aarch64-sve-builtins.h
\$(srcdir)/config/aarch64/aarch64-sve-builtins.cc"
target_has_targetm_common=yes
;;
diff --git a/gcc/config/aarch64/aarch64-passes.def
b/gcc/config/aarch64/aarch64-passes.def
index 6ace797b738..fa79e8adca8 100644
--- a/gcc/config/aarch64/aarch64-passes.def
+++ b/gcc/config/aarch64/aarch64-passes.def
@@ -23,3 +23,4 @@ INSERT_PASS_BEFORE (pass_reorder_blocks, 1,
pass_track_speculation);
INSERT_PASS_AFTER (pass_machine_reorg, 1, pass_tag_collision_avoidance);
INSERT_PASS_BEFORE (pass_shorten_branches, 1, pass_insert_bti);
INSERT_PASS_AFTER (pass_if_after_combine, 1, pass_cc_fusion);
+INSERT_PASS_AFTER (pass_peephole2, 1, pass_avoid_store_forwarding);
diff --git a/gcc/config/aarch64/aarch64-protos.h
b/gcc/config/aarch64/aarch64-protos.h
index 36d6c688bc8..aee074e58dd 100644
--- a/gcc/config/aarch64/aarch64-protos.h
+++ b/gcc/config/aarch64/aarch64-protos.h
@@ -1051,6 +1051,7 @@ rtl_opt_pass *make_pass_track_speculation (gcc::context
*);
rtl_opt_pass *make_pass_tag_collision_avoidance (gcc::context *);
rtl_opt_pass *make_pass_insert_bti (gcc::context *ctxt);
rtl_opt_pass *make_pass_cc_fusion (gcc::context *ctxt);
+rtl_opt_pass *make_pass_avoid_store_forwarding (gcc::context *ctxt);
poly_uint64 aarch64_regmode_natural_size (machine_mode);
diff --git a/gcc/config/aarch64/aarch64-store-forwarding.cc
b/gcc/config/aarch64/aarch64-store-forwarding.cc
new file mode 100644
index 00000000000..50996874883
--- /dev/null
+++ b/gcc/config/aarch64/aarch64-store-forwarding.cc
@@ -0,0 +1,323 @@
+/* Avoid store forwarding optimization pass.
+ Copyright (C) 2023 Free Software Foundation, Inc.
+ Contributed by VRULL GmbH.
+
+ This file is part of GCC.
+
+ GCC is free software; you can redistribute it and/or modify it
+ under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3, or (at your option)
+ any later version.
+
+ GCC is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GCC; see the file COPYING3. If not see
+ <http://www.gnu.org/licenses/>. */
+
+#define IN_TARGET_CODE 1
+
+#include "config.h"
+#define INCLUDE_VECTOR
+#define INCLUDE_MAP
+#include "system.h"
+#include "coretypes.h"
+#include "backend.h"
+#include "rtl.h"
+#include "alias.h"
+#include "rtlanal.h"
+#include "tree-pass.h"
+#include "cselib.h"
+
+/* This is an RTL pass that detects store forwarding from stores to larger
+ loads (load pairs). For example, it can transform cases like
+
+ str d5, [sp, #320]
+ fmul d5, d31, d29
+ ldp d31, d17, [sp, #312] # Large load from small store
+
+ to
+
+ str d5, [sp, #320]
+ fmul d5, d31, d29
+ ldr d31, [sp, #312]
+ ldr d17, [sp, #320]
+
+ Design: The pass follows a straightforward design. It starts by
+ initializing the alias analysis and the cselib. Both of these are used to
+ find stores and larger loads with overlapping addresses, which are
+ candidates for store forwarding optimizations. It then scans on basic block
+ level to find stores that forward to larger loads and handles them
+ accordingly as described in the above example. Finally, the alias analysis
+ and the cselib library are closed. */
+
+typedef std::vector<std::pair<rtx_insn *, rtx>> vec_rtx_pair;
+typedef std::map<rtx, uint32_t> map_rtx_dist;
+
+/* Statistics counters. */
+static unsigned int stats_store_count = 0;
+static unsigned int stats_ldp_count = 0;
+static unsigned int stats_ssll_count = 0;
+static unsigned int stats_transformed_count = 0;
+
+/* Default. */
+static rtx dummy;
+static bool is_store (rtx expr, rtx &op_0=dummy);
+static bool is_load (rtx expr, rtx &op_1=dummy);
+
+/* Return true if SET expression EXPR is a store; otherwise false. OP_0 will
+ contain the MEM operand of the store. */
+
+static bool
+is_store (rtx expr, rtx &op_0)
+{
+ op_0 = SET_DEST (expr);
+
+ if (GET_CODE (op_0) == ZERO_EXTEND
+ || GET_CODE (op_0) == SIGN_EXTEND)
+ op_0 = XEXP (op_0, 0);
+
+ return MEM_P (op_0);
+}
+
+/* Return true if SET expression EXPR is a load; otherwise false. OP_1 will
+ contain the MEM operand of the load. */
+
+static bool
+is_load (rtx expr, rtx &op_1)
+{
+ op_1 = SET_SRC (expr);
+
+ if (GET_CODE (op_1) == ZERO_EXTEND
+ || GET_CODE (op_1) == SIGN_EXTEND)
+ op_1 = XEXP (op_1, 0);
+
+ return MEM_P (op_1);
+}
+
+/* Check the maximum instruction distance threshold and if crossed, remove the
+ store from STORE_EXPRS. DISTANCES contains the intruction distances. */
+
+void
+update_store_load_distances (vec_rtx_pair &store_exprs, map_rtx_dist
&distances)
+{
+ for (auto iter = store_exprs.begin (); iter < store_exprs.end ();)
+ {
+ (distances[(*iter).second])++;
+ iter = distances[(*iter).second]
+ > (uint32_t) aarch64_store_forwarding_threshold_param
+ ? store_exprs.erase (iter) : iter + 1;
+ }
+}
+
+/* Return true if STORE_MEM is forwarding to LOAD_MEM; otherwise false. */
+
+static bool
+is_forwarding (rtx store_mem, rtx load_mem)
+{
+ gcc_checking_assert (MEM_P (store_mem) && MEM_P (load_mem));
+
+ rtx store_mem_addr = canon_rtx (get_addr (XEXP (store_mem, 0)));
+ rtx load_mem_addr = canon_rtx (get_addr (XEXP (load_mem, 0)));
+
+ return rtx_equal_for_cselib_1 (store_mem_addr,
+ load_mem_addr,
+ GET_MODE (store_mem), 0);
+}
+
+/* Return true if INSN is a load pair, preceded by a store forwarding to it;
+ otherwise false. STORE_EXPRS contains the stores. */
+
+static bool
+is_small_store_to_large_load (vec_rtx_pair &store_exprs, rtx_insn *insn)
+{
+ unsigned int load_count = 0;
+ bool forwarding = false;
+ rtx expr = PATTERN (insn);
+
+ if (GET_CODE (expr) != PARALLEL
+ || XVECLEN (expr, 0) != 2)
+ return false;
+
+ for (int i = 0; i < XVECLEN (expr, 0); i++)
+ {
+ rtx op_1;
+ rtx out_exp = XVECEXP (expr, 0, i);
+
+ if (GET_CODE (out_exp) != SET)
+ continue;
+
+ if (!is_load (out_exp, op_1))
+ continue;
+
+ load_count++;
+
+ for (std::pair<rtx_insn *, rtx> str : store_exprs)
+ {
+ if (!is_forwarding (XEXP (str.second, 0), op_1))
+ continue;
+
+ if (dump_file)
+ {
+ fprintf (dump_file,
+ "Store forwarding to PARALLEL with loads:\n");
+ fprintf (dump_file, " From: ");
+ print_rtl_single (dump_file, str.first);
+ fprintf (dump_file, " To: ");
+ print_rtl_single (dump_file, insn);
+ }
+
+ forwarding = true;
+ }
+ }
+
+ if (load_count == 2)
+ stats_ldp_count++;
+
+ return load_count == 2 && forwarding;
+}
+
+/* Break a load pair into its 2 distinct loads, except if the base source
+ address to load from is overwriten in the first load. INSN should be the
+ PARALLEL of the load pair. */
+
+static void
+break_ldp (rtx_insn *insn)
+{
+ rtx expr = PATTERN (insn);
+
+ gcc_checking_assert (GET_CODE (expr) == PARALLEL && XVECLEN (expr, 0) == 2);
+
+ rtx load_0 = XVECEXP (expr, 0, 0);
+ rtx load_1 = XVECEXP (expr, 0, 1);
+
+ gcc_checking_assert (is_load (load_0) && is_load (load_1));
+
+ /* The base address was overwriten in the first load. */
+ if (reg_mentioned_p (SET_DEST (load_0), SET_SRC (load_1)))
+ return;
+
+ emit_insn_before (load_0, insn);
+ emit_insn_before (load_1, insn);
+ remove_insn (insn);
+
+ stats_transformed_count++;
+}
+
+static void
+scan_and_transform_bb_level ()
+{
+ rtx_insn *insn, *next;
+ basic_block bb;
+ FOR_EACH_BB_FN (bb, cfun)
+ {
+ vec_rtx_pair store_exprs;
+ map_rtx_dist store_cnt_byte_dist;
+ for (insn = BB_HEAD (bb); insn != NEXT_INSN (BB_END (bb)); insn = next)
+ {
+ next = NEXT_INSN (insn);
+
+ /* If we cross a CALL_P insn, clear the vectors, because the
+ small-store-to-large-load is unlikely to cause performance
+ difference. */
+ if (CALL_P (insn))
+ {
+ store_exprs.clear ();
+ store_cnt_byte_dist.clear ();
+ }
+
+ if (!NONJUMP_INSN_P (insn))
+ continue;
+
+ cselib_process_insn (insn);
+
+ rtx expr = single_set (insn);
+
+ /* If a store is encountered, push it to the store_exprs vector to
+ check it later. */
+ if (expr && is_store (expr))
+ {
+ store_exprs.push_back ({insn, expr});
+
+ /* The store insn shouldn't have been encountered before. */
+ gcc_checking_assert (store_cnt_byte_dist.find (expr)
+ == store_cnt_byte_dist.end ());
+ store_cnt_byte_dist.insert ({ expr, 0 });
+ stats_store_count++;
+ }
+
+ /* Check for small-store-to-large-load. */
+ if (is_small_store_to_large_load (store_exprs, insn))
+ {
+ stats_ssll_count++;
+ break_ldp (insn);
+ }
+
+ update_store_load_distances (store_exprs, store_cnt_byte_dist);
+ }
+ }
+}
+
+static void
+execute_avoid_store_forwarding ()
+{
+ init_alias_analysis ();
+ cselib_init (0);
+ scan_and_transform_bb_level ();
+ end_alias_analysis ();
+ cselib_finish ();
+ statistics_counter_event (cfun, "Number of stores identified: ",
+ stats_store_count);
+ statistics_counter_event (cfun, "Number of load pairs identified: ",
+ stats_ldp_count);
+ statistics_counter_event (cfun,
+ "Number of forwarding cases identified: ",
+ stats_ssll_count);
+ statistics_counter_event (cfun, "Number of trasformed cases: ",
+ stats_transformed_count);
+}
+
+const pass_data pass_data_avoid_store_forwarding =
+{
+ RTL_PASS, /* type. */
+ "avoid_store_forwarding", /* name. */
+ OPTGROUP_NONE, /* optinfo_flags. */
+ TV_NONE, /* tv_id. */
+ 0, /* properties_required. */
+ 0, /* properties_provided. */
+ 0, /* properties_destroyed. */
+ 0, /* todo_flags_start. */
+ 0 /* todo_flags_finish. */
+};
+
+class pass_avoid_store_forwarding : public rtl_opt_pass
+{
+public:
+ pass_avoid_store_forwarding (gcc::context *ctxt)
+ : rtl_opt_pass (pass_data_avoid_store_forwarding, ctxt)
+ {}
+
+ /* opt_pass methods: */
+ virtual bool gate (function *)
+ {
+ return aarch64_flag_avoid_store_forwarding && optimize >= 2;
+ }
+
+ virtual unsigned int execute (function *)
+ {
+ execute_avoid_store_forwarding ();
+ return 0;
+ }
+
+}; // class pass_avoid_store_forwarding
+
+/* Create a new avoid store forwarding pass instance. */
+
+rtl_opt_pass *
+make_pass_avoid_store_forwarding (gcc::context *ctxt)
+{
+ return new pass_avoid_store_forwarding (ctxt);
+}
diff --git a/gcc/config/aarch64/aarch64.opt b/gcc/config/aarch64/aarch64.opt
index f5a518202a1..a9e944a272f 100644
--- a/gcc/config/aarch64/aarch64.opt
+++ b/gcc/config/aarch64/aarch64.opt
@@ -304,6 +304,10 @@ moutline-atomics
Target Var(aarch64_flag_outline_atomics) Init(2) Save
Generate local calls to out-of-line atomic operations.
+mavoid-store-forwarding
+Target Bool Var(aarch64_flag_avoid_store_forwarding) Init(0) Optimization
+Avoid store forwarding to load pairs.
+
-param=aarch64-sve-compare-costs=
Target Joined UInteger Var(aarch64_sve_compare_costs) Init(1) IntegerRange(0,
1) Param
When vectorizing for SVE, consider using unpacked vectors for smaller elements
and use the cost model to pick the cheapest approach. Also use the cost model
to choose between SVE and Advanced SIMD vectorization.
@@ -360,3 +364,8 @@ Enum(aarch64_ldp_stp_policy) String(never)
Value(AARCH64_LDP_STP_POLICY_NEVER)
EnumValue
Enum(aarch64_ldp_stp_policy) String(aligned)
Value(AARCH64_LDP_STP_POLICY_ALIGNED)
+
+-param=aarch64-store-forwarding-threshold=
+Target Joined UInteger Var(aarch64_store_forwarding_threshold_param) Init(20)
Param
+Maximum instruction distance allowed between a store and a load pair for this
to be
+considered a candidate to avoid when using aarch64-avoid-store-forwarding.
diff --git a/gcc/config/aarch64/t-aarch64 b/gcc/config/aarch64/t-aarch64
index a9a244ab6d6..7639b50358d 100644
--- a/gcc/config/aarch64/t-aarch64
+++ b/gcc/config/aarch64/t-aarch64
@@ -176,6 +176,16 @@ aarch64-cc-fusion.o:
$(srcdir)/config/aarch64/aarch64-cc-fusion.cc \
$(COMPILER) -c $(ALL_COMPILERFLAGS) $(ALL_CPPFLAGS) $(INCLUDES) \
$(srcdir)/config/aarch64/aarch64-cc-fusion.cc
+aarch64-store-forwarding.o: \
+ $(srcdir)/config/aarch64/aarch64-store-forwarding.cc \
+ $(CONFIG_H) $(SYSTEM_H) $(TM_H) $(REGS_H) insn-config.h $(RTL_BASE_H) \
+ dominance.h cfg.h cfganal.h $(BASIC_BLOCK_H) $(INSN_ATTR_H) $(RECOG_H) \
+ output.h hash-map.h $(DF_H) $(OBSTACK_H) $(TARGET_H) $(RTL_H) \
+ $(CONTEXT_H) $(TREE_PASS_H) regrename.h \
+ $(srcdir)/config/aarch64/aarch64-protos.h
+ $(COMPILER) -c $(ALL_COMPILERFLAGS) $(ALL_CPPFLAGS) $(INCLUDES) \
+ $(srcdir)/config/aarch64/aarch64-store-forwarding.cc
+
comma=,
MULTILIB_OPTIONS = $(subst $(comma),/, $(patsubst %, mabi=%, $(subst
$(comma),$(comma)mabi=,$(TM_MULTILIB_CONFIG))))
MULTILIB_DIRNAMES = $(subst $(comma), ,$(TM_MULTILIB_CONFIG))
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index bc9f4f70914..275dde8d541 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -796,7 +796,7 @@ Objective-C and Objective-C++ Dialects}.
-moverride=@var{string} -mverbose-cost-dump
-mstack-protector-guard=@var{guard} -mstack-protector-guard-reg=@var{sysreg}
-mstack-protector-guard-offset=@var{offset} -mtrack-speculation
--moutline-atomics }
+-moutline-atomics -mavoid-store-forwarding}
@emph{Adapteva Epiphany Options}
@gccoptlist{-mhalf-reg-file -mprefer-short-insn-regs
@@ -16636,6 +16636,11 @@ With @option{--param=aarch64-stp-policy=never}, do not
emit stp.
With @option{--param=aarch64-stp-policy=aligned}, emit stp only if the
source pointer is aligned to at least double the alignment of the type.
+@item aarch64-store-forwarding-threshold
+Maximum allowed instruction distance between a store and a load pair for
+this to be considered a candidate to avoid when using
+aarch64-avoid-store-forwarding.
+
@item aarch64-loop-vect-issue-rate-niters
The tuning for some AArch64 CPUs tries to take both latencies and issue
rates into account when deciding whether a loop should be vectorized
@@ -20628,6 +20633,11 @@ Generate code which uses only the general-purpose
registers. This will prevent
the compiler from using floating-point and Advanced SIMD registers but will not
impose any restrictions on the assembler.
+@item -mavoid-store-forwarding
+@itemx -mno-avoid-store-forwarding
+Avoid store forwarding to load pairs.
+@option{-mavoid-store-forwarding} at levels @option{-O2}, @option{-O3}.
+
@opindex mlittle-endian
@item -mlittle-endian
Generate little-endian code. This is the default when GCC is configured for an
diff --git a/gcc/testsuite/gcc.target/aarch64/ldp_ssll_no_overlap_address.c
b/gcc/testsuite/gcc.target/aarch64/ldp_ssll_no_overlap_address.c
new file mode 100644
index 00000000000..b77de6c64b6
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/ldp_ssll_no_overlap_address.c
@@ -0,0 +1,33 @@
+/* { dg-options "-O2 -mcpu=generic -mavoid-store-forwarding" } */
+
+#include <stdint.h>
+
+typedef int v4si __attribute__ ((vector_size (16)));
+
+/* Different address, same offset, no overlap */
+
+#define LDP_SSLL_NO_OVERLAP_ADDRESS(TYPE) \
+TYPE ldp_ssll_no_overlap_address_##TYPE(TYPE *ld_arr, TYPE *st_arr, TYPE
*st_arr_2, TYPE i, TYPE dummy){ \
+ TYPE r, y; \
+ st_arr[0] = i; \
+ ld_arr[0] = dummy; \
+ r = st_arr_2[0]; \
+ y = st_arr_2[1]; \
+ return r + y; \
+}
+
+LDP_SSLL_NO_OVERLAP_ADDRESS(uint32_t)
+LDP_SSLL_NO_OVERLAP_ADDRESS(uint64_t)
+LDP_SSLL_NO_OVERLAP_ADDRESS(int32_t)
+LDP_SSLL_NO_OVERLAP_ADDRESS(int64_t)
+LDP_SSLL_NO_OVERLAP_ADDRESS(int)
+LDP_SSLL_NO_OVERLAP_ADDRESS(long)
+LDP_SSLL_NO_OVERLAP_ADDRESS(float)
+LDP_SSLL_NO_OVERLAP_ADDRESS(double)
+LDP_SSLL_NO_OVERLAP_ADDRESS(v4si)
+
+/* { dg-final { scan-assembler-times "ldp\tw\[0-9\]+, w\[0-9\]" 3 } } */
+/* { dg-final { scan-assembler-times "ldp\tx\[0-9\]+, x\[0-9\]" 3 } } */
+/* { dg-final { scan-assembler-times "ldp\ts\[0-9\]+, s\[0-9\]" 1 } } */
+/* { dg-final { scan-assembler-times "ldp\td\[0-9\]+, d\[0-9\]" 1 } } */
+/* { dg-final { scan-assembler-times "ldp\tq\[0-9\]+, q\[0-9\]" 1 } } */
diff --git a/gcc/testsuite/gcc.target/aarch64/ldp_ssll_no_overlap_offset.c
b/gcc/testsuite/gcc.target/aarch64/ldp_ssll_no_overlap_offset.c
new file mode 100644
index 00000000000..f1b3a66abfd
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/ldp_ssll_no_overlap_offset.c
@@ -0,0 +1,33 @@
+/* { dg-options "-O2 -mcpu=generic -mavoid-store-forwarding" } */
+
+#include <stdint.h>
+
+typedef int v4si __attribute__ ((vector_size (16)));
+
+/* Same address, different offset, no overlap */
+
+#define LDP_SSLL_NO_OVERLAP_OFFSET(TYPE) \
+TYPE ldp_ssll_no_overlap_offset_##TYPE(TYPE *ld_arr, TYPE *st_arr, TYPE i,
TYPE dummy){ \
+ TYPE r, y; \
+ st_arr[0] = i; \
+ ld_arr[0] = dummy; \
+ r = st_arr[10]; \
+ y = st_arr[11]; \
+ return r + y; \
+}
+
+LDP_SSLL_NO_OVERLAP_OFFSET(uint32_t)
+LDP_SSLL_NO_OVERLAP_OFFSET(uint64_t)
+LDP_SSLL_NO_OVERLAP_OFFSET(int32_t)
+LDP_SSLL_NO_OVERLAP_OFFSET(int64_t)
+LDP_SSLL_NO_OVERLAP_OFFSET(int)
+LDP_SSLL_NO_OVERLAP_OFFSET(long)
+LDP_SSLL_NO_OVERLAP_OFFSET(float)
+LDP_SSLL_NO_OVERLAP_OFFSET(double)
+LDP_SSLL_NO_OVERLAP_OFFSET(v4si)
+
+/* { dg-final { scan-assembler-times "ldp\tw\[0-9\]+, w\[0-9\]" 3 } } */
+/* { dg-final { scan-assembler-times "ldp\tx\[0-9\]+, x\[0-9\]" 3 } } */
+/* { dg-final { scan-assembler-times "ldp\ts\[0-9\]+, s\[0-9\]" 1 } } */
+/* { dg-final { scan-assembler-times "ldp\td\[0-9\]+, d\[0-9\]" 1 } } */
+/* { dg-final { scan-assembler-times "ldp\tq\[0-9\]+, q\[0-9\]" 1 } } */
diff --git a/gcc/testsuite/gcc.target/aarch64/ldp_ssll_overlap.c
b/gcc/testsuite/gcc.target/aarch64/ldp_ssll_overlap.c
new file mode 100644
index 00000000000..8d5ce5cc87e
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/ldp_ssll_overlap.c
@@ -0,0 +1,33 @@
+/* { dg-options "-O2 -mcpu=generic -mavoid-store-forwarding" } */
+
+#include <stdint.h>
+
+typedef int v4si __attribute__ ((vector_size (16)));
+
+/* Same address, same offset, overlap */
+
+#define LDP_SSLL_OVERLAP(TYPE) \
+TYPE ldp_ssll_overlap_##TYPE(TYPE *ld_arr, TYPE *st_arr, TYPE i, TYPE dummy){ \
+ TYPE r, y; \
+ st_arr[0] = i; \
+ ld_arr[0] = dummy; \
+ r = st_arr[0]; \
+ y = st_arr[1]; \
+ return r + y; \
+}
+
+LDP_SSLL_OVERLAP(uint32_t)
+LDP_SSLL_OVERLAP(uint64_t)
+LDP_SSLL_OVERLAP(int32_t)
+LDP_SSLL_OVERLAP(int64_t)
+LDP_SSLL_OVERLAP(int)
+LDP_SSLL_OVERLAP(long)
+LDP_SSLL_OVERLAP(float)
+LDP_SSLL_OVERLAP(double)
+LDP_SSLL_OVERLAP(v4si)
+
+/* { dg-final { scan-assembler-times "ldp\tw\[0-9\]+, w\[0-9\]" 0 } } */
+/* { dg-final { scan-assembler-times "ldp\tx\[0-9\]+, x\[0-9\]" 0 } } */
+/* { dg-final { scan-assembler-times "ldp\ts\[0-9\]+, s\[0-9\]" 0 } } */
+/* { dg-final { scan-assembler-times "ldp\td\[0-9\]+, d\[0-9\]" 0 } } */
+/* { dg-final { scan-assembler-times "ldp\tq\[0-9\]+, q\[0-9\]" 0 } } */
--
2.41.0
