[libc] Add memmove benchmarks

This patch enables the benchmarking of `memmove`.
Ideally, this should be submitted before D114637.

Differential Revision: https://reviews.llvm.org/D114694

libc/benchmarks/CMakeLists.txt

@@ -172,11 +172,12 @@ function(add_libc_multi_impl_benchmark name)
   endforeach()
 endfunction()
 
-add_libc_multi_impl_benchmark(memcpy)
+add_libc_multi_impl_benchmark(bcmp)
-add_libc_multi_impl_benchmark(memset)
 add_libc_multi_impl_benchmark(bzero)
 add_libc_multi_impl_benchmark(memcmp)
-add_libc_multi_impl_benchmark(bcmp)
+add_libc_multi_impl_benchmark(memcpy)
+add_libc_multi_impl_benchmark(memmove)
+add_libc_multi_impl_benchmark(memset)
 
 #==============================================================================
 # Google Benchmarking tool
@@ -199,6 +200,7 @@ target_link_libraries(libc.benchmarks.memory_functions.opt_host
   libc.src.string.memcpy_opt_host
   libc.src.string.memset_opt_host
   libc.src.string.bzero_opt_host
+  libc.src.string.memmove_opt_host
   benchmark_main
 )
 

libc/benchmarks/LibcDefaultImplementations.cpp

@@ -5,6 +5,7 @@
 namespace __llvm_libc {
 
 extern void *memcpy(void *__restrict, const void *__restrict, size_t);
+extern void *memmove(void *, const void *, size_t);
 extern void *memset(void *, int, size_t);
 extern void bzero(void *, size_t);
 extern int memcmp(const void *, const void *, size_t);
@@ -17,6 +18,7 @@ extern int bcmp(const void *, const void *, size_t);
 using llvm::libc_benchmarks::BzeroConfiguration;
 using llvm::libc_benchmarks::MemcmpOrBcmpConfiguration;
 using llvm::libc_benchmarks::MemcpyConfiguration;
+using llvm::libc_benchmarks::MemmoveConfiguration;
 using llvm::libc_benchmarks::MemsetConfiguration;
 
 llvm::ArrayRef<MemcpyConfiguration> getMemcpyConfigurations() {
@@ -24,6 +26,11 @@ llvm::ArrayRef<MemcpyConfiguration> getMemcpyConfigurations() {
       {__llvm_libc::memcpy, "__llvm_libc::memcpy"}};
   return llvm::makeArrayRef(kMemcpyConfigurations);
 }
+llvm::ArrayRef<MemmoveConfiguration> getMemmoveConfigurations() {
+  static constexpr MemmoveConfiguration kMemmoveConfigurations[] = {
+      {__llvm_libc::memmove, "__llvm_libc::memmove"}};
+  return llvm::makeArrayRef(kMemmoveConfigurations);
+}
 llvm::ArrayRef<MemcmpOrBcmpConfiguration> getMemcmpConfigurations() {
   static constexpr MemcmpOrBcmpConfiguration kMemcmpConfiguration[] = {
       {__llvm_libc::memcmp, "__llvm_libc::memcmp"}};

libc/benchmarks/LibcFunctionPrototypes.h

@@ -14,6 +14,12 @@ struct MemcpyConfiguration {
   llvm::StringRef Name;
 };
 
+using MemmoveFunction = void *(*)(void *, const void *, size_t);
+struct MemmoveConfiguration {
+  MemmoveFunction Function;
+  llvm::StringRef Name;
+};
+
 using MemsetFunction = void *(*)(void *, int, size_t);
 struct MemsetConfiguration {
   MemsetFunction Function;

libc/benchmarks/LibcMemoryBenchmark.cpp

@@ -108,6 +108,9 @@ CopySetup::CopySetup()
     : ParameterBatch(2), SrcBuffer(ParameterBatch::BufferSize),
       DstBuffer(ParameterBatch::BufferSize) {}
 
+MoveSetup::MoveSetup()
+    : ParameterBatch(3), Buffer(ParameterBatch::BufferSize * 3) {}
+
 ComparisonSetup::ComparisonSetup()
     : ParameterBatch(2), LhsBuffer(ParameterBatch::BufferSize),
       RhsBuffer(ParameterBatch::BufferSize) {

libc/benchmarks/LibcMemoryBenchmark.h

@@ -206,6 +206,24 @@ private:
   AlignedBuffer DstBuffer;
 };
 
+/// Provides source and destination buffers for the Move operation as well as
+/// the associated size distributions.
+struct MoveSetup : public ParameterBatch {
+  MoveSetup();
+
+  inline static const ArrayRef<MemorySizeDistribution> getDistributions() {
+    return getMemmoveSizeDistributions();
+  }
+
+  inline void *Call(ParameterType Parameter, MemmoveFunction Memmove) {
+    return Memmove(Buffer + ParameterBatch::BufferSize / 3,
+                   Buffer + Parameter.OffsetBytes, Parameter.SizeBytes);
+  }
+
+private:
+  AlignedBuffer Buffer;
+};
+
 /// Provides destination buffer for the Set operation as well as the associated
 /// size distributions.
 struct SetSetup : public ParameterBatch {

libc/benchmarks/LibcMemoryBenchmarkMain.cpp

@@ -24,6 +24,7 @@
 namespace __llvm_libc {
 
 extern void *memcpy(void *__restrict, const void *__restrict, size_t);
+extern void *memmove(void *, const void *, size_t);
 extern void *memset(void *, int, size_t);
 extern void bzero(void *, size_t);
 extern int memcmp(const void *, const void *, size_t);
@@ -68,6 +69,9 @@ static cl::opt<uint32_t>
 #if defined(LIBC_BENCHMARK_FUNCTION_MEMCPY)
 #define LIBC_BENCHMARK_FUNCTION LIBC_BENCHMARK_FUNCTION_MEMCPY
 using BenchmarkSetup = CopySetup;
+#elif defined(LIBC_BENCHMARK_FUNCTION_MEMMOVE)
+#define LIBC_BENCHMARK_FUNCTION LIBC_BENCHMARK_FUNCTION_MEMMOVE
+using BenchmarkSetup = MoveSetup;
 #elif defined(LIBC_BENCHMARK_FUNCTION_MEMSET)
 #define LIBC_BENCHMARK_FUNCTION LIBC_BENCHMARK_FUNCTION_MEMSET
 using BenchmarkSetup = SetSetup;

libc/benchmarks/LibcMemoryGoogleBenchmarkMain.cpp

@@ -17,8 +17,10 @@ using llvm::libc_benchmarks::ComparisonSetup;
 using llvm::libc_benchmarks::CopySetup;
 using llvm::libc_benchmarks::MemcmpOrBcmpConfiguration;
 using llvm::libc_benchmarks::MemcpyConfiguration;
+using llvm::libc_benchmarks::MemmoveConfiguration;
 using llvm::libc_benchmarks::MemorySizeDistribution;
 using llvm::libc_benchmarks::MemsetConfiguration;
+using llvm::libc_benchmarks::MoveSetup;
 using llvm::libc_benchmarks::OffsetDistribution;
 using llvm::libc_benchmarks::SetSetup;
 
@@ -94,6 +96,10 @@ extern llvm::ArrayRef<MemcpyConfiguration> getMemcpyConfigurations();
 BENCHMARK_MEMORY_FUNCTION(BM_Memcpy, CopySetup, MemcpyConfiguration,
                           getMemcpyConfigurations());
 
+extern llvm::ArrayRef<MemmoveConfiguration> getMemmoveConfigurations();
+BENCHMARK_MEMORY_FUNCTION(BM_Memmove, MoveSetup, MemmoveConfiguration,
+                          getMemmoveConfigurations());
+
 extern llvm::ArrayRef<MemcmpOrBcmpConfiguration> getMemcmpConfigurations();
 BENCHMARK_MEMORY_FUNCTION(BM_Memcmp, ComparisonSetup, MemcmpOrBcmpConfiguration,
                           getMemcmpConfigurations());

libc/benchmarks/automemcpy/lib/CodeGen.cpp

@@ -548,6 +548,7 @@ static void Serialize(raw_ostream &Stream,
   Stream << "using llvm::libc_benchmarks::BzeroConfiguration;\n";
   Stream << "using llvm::libc_benchmarks::MemcmpOrBcmpConfiguration;\n";
   Stream << "using llvm::libc_benchmarks::MemcpyConfiguration;\n";
+  Stream << "using llvm::libc_benchmarks::MemmoveConfiguration;\n";
   Stream << "using llvm::libc_benchmarks::MemsetConfiguration;\n";
   Stream << "\n";
   Stream << "namespace __llvm_libc {\n";
@@ -599,6 +600,11 @@ template <BzeroStub Foo> void Wrap(void *dst, size_t size) {
 }
 )";
   codegen::configurations::Serialize(Stream, FunctionType::BZERO, Descriptors);
+  Stream << R"(
+llvm::ArrayRef<MemmoveConfiguration> getMemmoveConfigurations() {
+  return {};
+}
+)";
   Stream << "// Functions : " << Descriptors.size() << "\n";
 }
 

libc/src/string/CMakeLists.txt

@@ -37,17 +37,6 @@ add_entrypoint_object(
     .string_utils
 )
 
-add_entrypoint_object(
-  memmove
-  SRCS
-    memmove.cpp
-  HDRS
-    memmove.h
-  DEPENDS
-    libc.src.__support.integer_operations
-    .memory_utils.memcpy_implementation
-)
-
 add_entrypoint_object(
   memrchr
   SRCS
@@ -404,6 +393,42 @@ else()
   add_memcpy(memcpy)
 endif()
 
+# ------------------------------------------------------------------------------
+# memmove
+# ------------------------------------------------------------------------------
+
+function(add_memmove memmove_name)
+  add_implementation(memmove ${memmove_name}
+    SRCS ${LIBC_SOURCE_DIR}/src/string/memmove.cpp
+    HDRS ${LIBC_SOURCE_DIR}/src/string/memmove.h
+    DEPENDS
+      .memory_utils.memory_utils
+      .memory_utils.memcpy_implementation
+      libc.include.string
+    COMPILE_OPTIONS
+      -fno-builtin
+    ${ARGN}
+  )
+endfunction()
+
+if(${LIBC_TARGET_ARCHITECTURE_IS_X86})
+  add_memmove(memmove_x86_64_opt_sse2   COMPILE_OPTIONS -march=k8             REQUIRE SSE2)
+  add_memmove(memmove_x86_64_opt_sse4   COMPILE_OPTIONS -march=nehalem        REQUIRE SSE4_2)
+  add_memmove(memmove_x86_64_opt_avx2   COMPILE_OPTIONS -march=haswell        REQUIRE AVX2)
+  add_memmove(memmove_x86_64_opt_avx512 COMPILE_OPTIONS -march=skylake-avx512 REQUIRE AVX512F)
+  add_memmove(memmove_opt_host          COMPILE_OPTIONS ${LIBC_COMPILE_OPTIONS_NATIVE})
+  add_memmove(memmove)
+elseif(${LIBC_TARGET_ARCHITECTURE_IS_AARCH64})
+  # Disable tail merging as it leads to lower performance.
+  # Note that '-mllvm' needs to be prefixed with 'SHELL:' to prevent CMake flag deduplication.
+  add_memmove(memmove_opt_host          COMPILE_OPTIONS ${LIBC_COMPILE_OPTIONS_NATIVE}
+                                        COMPILE_OPTIONS "SHELL:-mllvm --tail-merge-threshold=0")
+  add_memmove(memmove                   COMPILE_OPTIONS "SHELL:-mllvm --tail-merge-threshold=0")
+else()
+  add_memmove(memmove_opt_host          COMPILE_OPTIONS ${LIBC_COMPILE_OPTIONS_NATIVE})
+  add_memmove(memmove)
+endif()
+
 # ------------------------------------------------------------------------------
 # memset
 # ------------------------------------------------------------------------------