PNaCl: Test support for GCC/LLVM vector extensions

tests/simd/vector_extension.c

+/*
+ * Copyright (c) 2014 The Native Client Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/*
+ * Test that the GCC/LLVM vector extensions can be used from C code.
+ * http://gcc.gnu.org/onlinedocs/gcc/Vector-Extensions.html
+ * http://clang.llvm.org/docs/LanguageExtensions.html
+ */
+
+#include "native_client/src/include/nacl_macros.h"
+
+#include <stdint.h>
+#include <stdio.h>
+

[nfullagar1, 2014/04/16 23:04:57]

can you add a description/goal of what this file is testing?  It appears to be a
combination of does-it-compile & crash/no-crash at runtime.  The nested macros
and use of ## may obfuscate failure cases and make them harder to track down.

[JF, 2014/04/17 00:05:44]

Done.

+/*
+ * Basic types that are supported inside vectors.
+ *
+ * TODO(jfb) Handle 64-bit int and double.
+ */
+typedef int8_t I8;
+typedef uint8_t U8;
+typedef int16_t I16;
+typedef uint16_t U16;
+typedef int32_t I32;
+typedef uint32_t U32;
+typedef float F32;
+
+/*
+ *
+ * The GCC/LLVM vector extensions represent the results of comparisons
+ * as a vector of all-ones or all-zeros with the same vector bit width
+ * and number of elements. They must be treated differently than their
+ * corresponding type because floating-point values change their bit
+ * representation through assignments when they hold NaN values.
+ */
+typedef int8_t I8_BOOL;
+typedef int8_t U8_BOOL;
+typedef int16_t I16_BOOL;
+typedef int16_t U16_BOOL;
+typedef int32_t I32_BOOL;
+typedef int32_t U32_BOOL;
+typedef int32_t F32_BOOL;
+
+#define I8_FMT "i"
+#define U8_FMT "u"
+#define I16_FMT "i"
+#define U16_FMT "u"
+#define I32_FMT "i"
+#define U32_FMT "u"
+#define F32_FMT "f"
+
+/* All elements in a boolean vector should print as 0 or -1. */
+#define I8_BOOL_FMT "i"
+#define U8_BOOL_FMT "i"
+#define I16_BOOL_FMT "i"
+#define U16_BOOL_FMT "i"
+#define I32_BOOL_FMT "i"
+#define U32_BOOL_FMT "i"
+#define F32_BOOL_FMT "i"
+
+/* All supported vector types are currently 128-bit wide. */
+#define VEC_BYTES 16
+
+/* Vector types corresponding to each supported basic types. */
+typedef I8 VI8 __attribute__((vector_size(VEC_BYTES)));
+typedef U8 VU8 __attribute__((vector_size(VEC_BYTES)));
+typedef I16 VI16 __attribute__((vector_size(VEC_BYTES)));
+typedef U16 VU16 __attribute__((vector_size(VEC_BYTES)));
+typedef I32 VI32 __attribute__((vector_size(VEC_BYTES)));
+typedef U32 VU32 __attribute__((vector_size(VEC_BYTES)));
+typedef F32 VF32 __attribute__((vector_size(VEC_BYTES)));

[nfullagar1, 2014/04/16 23:04:57]

The names (ie 'I8') chosen here (and elsewhere) will clash once larger or
smaller vector (256 bit, 512, 64...) support becomes available.

[JF, 2014/04/17 00:05:44]

Agreed, we'll need to add width to the name once we get there.

+
+/* Boolean vector types generate by comparisons on each vector type. */
+typedef I8 VI8_BOOL __attribute__((vector_size(VEC_BYTES)));
+typedef I8 VU8_BOOL __attribute__((vector_size(VEC_BYTES)));
+typedef I16 VI16_BOOL __attribute__((vector_size(VEC_BYTES)));
+typedef I16 VU16_BOOL __attribute__((vector_size(VEC_BYTES)));
+typedef I32 VI32_BOOL __attribute__((vector_size(VEC_BYTES)));
+typedef I32 VU32_BOOL __attribute__((vector_size(VEC_BYTES)));
+typedef I32 VF32_BOOL __attribute__((vector_size(VEC_BYTES)));
+
+#define PRINT(TYPE, VEC)                                                \
+  do {                                                                  \
+    NACL_COMPILE_TIME_ASSERT(sizeof(V##TYPE) ==                         \
+                             VEC_BYTES); /* Vector must be 128 bits. */ \
+    NACL_COMPILE_TIME_ASSERT(sizeof(TYPE) ==                            \
+                             sizeof(VEC[0])); /* Type must match. */    \
+    printf("{");                                                        \
+    for (size_t i = 0; i != sizeof(V##TYPE) / sizeof(VEC[0]); ++i)      \
+      printf("%" TYPE##_FMT ",", VEC[i]);                               \
+    printf("}");                                                        \
+  } while (0)
+
+#define TEST_BINARY(TYPE, LHS, OP, RHS)                               \
+  do {                                                                \
+    NACL_COMPILE_TIME_ASSERT(sizeof(TYPE) ==                          \
+                             sizeof(LHS[0])); /* Types must match. */ \
+    NACL_COMPILE_TIME_ASSERT(sizeof(TYPE) ==                          \
+                             sizeof(RHS[0])); /* Types must match. */ \
+    const V##TYPE result = LHS OP RHS;                                \
+    printf(#TYPE " ");                                                \
+    PRINT(TYPE, LHS);                                                 \
+    printf(" %s ", #OP);                                              \
+    PRINT(TYPE, RHS);                                                 \
+    printf(" = ");                                                    \
+    PRINT(TYPE, result);                                              \
+    printf("\n");                                                     \
+  } while (0)
+
+#define TEST_BINARY_COMPARISON(TYPE, LHS, OP, RHS)                    \
+  do {                                                                \
+    NACL_COMPILE_TIME_ASSERT(sizeof(TYPE) ==                          \
+                             sizeof(LHS[0])); /* Types must match. */ \
+    NACL_COMPILE_TIME_ASSERT(sizeof(TYPE) ==                          \
+                             sizeof(RHS[0])); /* Types must match. */ \
+    const V##TYPE##_BOOL result = LHS OP RHS;                         \
+    printf(#TYPE " ");                                                \
+    PRINT(TYPE, LHS);                                                 \
+    printf(" %s ", #OP);                                              \
+    PRINT(TYPE, RHS);                                                 \
+    printf(" = ");                                                    \
+    PRINT(TYPE##_BOOL, result);                                       \
+    printf("\n");                                                     \
+  } while (0)
+
+#define TEST_UNARY(TYPE, OP, VAL)                                     \
+  do {                                                                \
+    NACL_COMPILE_TIME_ASSERT(sizeof(TYPE) ==                          \
+                             sizeof(VAL[0])); /* Types must match. */ \
+    const V##TYPE result = OP VAL;                                    \
+    printf(#TYPE " %s ", #OP);                                        \
+    PRINT(TYPE, VAL);                                                 \
+    printf(" = ");                                                    \
+    PRINT(TYPE, result);                                              \
+    printf("\n");                                                     \
+  } while (0)
+
+#define TEST_BINARY_FP(TYPE, LHS, RHS)          \
+  do {                                          \
+    TEST_BINARY(TYPE, LHS, +, RHS);             \
+    TEST_BINARY(TYPE, LHS, -, RHS);             \
+    TEST_BINARY(TYPE, LHS, *, RHS);             \
+    TEST_BINARY(TYPE, LHS, /, RHS);             \
+    TEST_BINARY_COMPARISON(TYPE, LHS, ==, RHS); \
+    TEST_BINARY_COMPARISON(TYPE, LHS, !=, RHS); \
+    TEST_BINARY_COMPARISON(TYPE, LHS, <, RHS);  \
+    TEST_BINARY_COMPARISON(TYPE, LHS, >, RHS);  \
+    TEST_BINARY_COMPARISON(TYPE, LHS, <=, RHS); \
+    TEST_BINARY_COMPARISON(TYPE, LHS, >=, RHS); \
+  } while (0)
+
+#define TEST_BINARY_INT(TYPE, LHS, RHS) \
+  do {                                  \
+    TEST_BINARY_FP(TYPE, LHS, RHS);     \
+    TEST_BINARY(TYPE, LHS, %, RHS);     \
+    TEST_BINARY(TYPE, LHS, &, RHS);     \
+    TEST_BINARY(TYPE, LHS, |, RHS);     \
+    TEST_BINARY(TYPE, LHS, ^, RHS);     \
+    TEST_BINARY(TYPE, LHS, <<, RHS);    \
+    TEST_BINARY(TYPE, LHS, >>, RHS);    \
+  } while (0)
+
+/*
+ * TODO(jfb) Pre/post ++/-- don't seem to be supported. Neither does !.
+ */
+#define TEST_UNARY_FP(TYPE, VAL) \
+  do {                           \
+    TEST_UNARY(TYPE, +, VAL);    \
+    TEST_UNARY(TYPE, -, VAL);    \
+  } while (0)
+
+#define TEST_UNARY_INT(TYPE, VAL) \
+  do {                            \
+    TEST_UNARY_FP(TYPE, VAL);     \
+    TEST_UNARY(TYPE, ~, VAL);     \
+  } while (0)
+
+/*
+ * Vector values used in tests.
+ *
+ * Initialize everything in a non-inlined function to make sure that
+ * nothing gets pre-computed.
+ */
+VI8 vi8[2];
+VU8 vu8[2];
+VI16 vi16[2];
+VU16 vu16[2];
+VI32 vi32[2];
+VU32 vu32[2];
+VF32 vf32[2];
+__attribute__((noinline)) void init(void) {
+  /*
+   * TODO(jfb) Test undefined behavior: shift bit bitwidth or larger,
+   *           and divide by zero.
+   */
+  vi8[0] = (VI8) {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16};
+  vi8[1] = (VI8) {2, 1, 1, 2, 3, 4, 5, 6, 7, 7, 6, 5, 4, 3, 2, 1};
+
+  vu8[0] = (VU8) {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16};
+  vu8[1] = (VU8) {2, 1, 1, 2, 3, 4, 5, 6, 7, 7, 6, 5, 4, 3, 2, 1};
+
+  vi16[0] = (VI16) {1, 2, 3, 4, 5, 6, 7, 8};
+  vi16[1] = (VI16) {1, 15, 14, 13, 12, 11, 10, 9};
+
+  vu16[0] = (VU16) {1, 2, 3, 4, 5, 6, 7, 8};
+  vu16[1] = (VU16) {1, 15, 14, 13, 12, 11, 10, 9};
+
+  vi32[0] = (VI32) {1, 2, 3, 4};
+  vi32[1] = (VI32) {16, 15, 14, 13};
+
+  vu32[0] = (VU32) {1, 2, 3, 4};
+  vu32[1] = (VU32) {16, 15, 14, 13};
+
+  vf32[0] = (VF32) {1, 2, 3, 4};
+  vf32[1] = (VF32) {16, 15, 14, 13};
+}
+
+__attribute__((noinline)) void test(void) {
+  TEST_BINARY_INT(I8, vi8[0], vi8[1]);
+  TEST_BINARY_INT(U8, vu8[0], vu8[1]);
+  TEST_BINARY_INT(I16, vi16[0], vi16[1]);
+  TEST_BINARY_INT(U16, vu16[0], vu16[1]);
+  TEST_BINARY_INT(I32, vi32[0], vi32[1]);
+  TEST_BINARY_INT(U32, vu32[0], vu32[1]);
+  TEST_BINARY_FP(F32, vf32[0], vf32[1]);
+
+  TEST_UNARY_INT(I8, vi8[0]);
+  TEST_UNARY_INT(U8, vu8[0]);
+  TEST_UNARY_INT(I16, vi16[0]);
+  TEST_UNARY_INT(U16, vu16[0]);
+  TEST_UNARY_INT(I32, vi32[0]);
+  TEST_UNARY_INT(U32, vu32[0]);
+  TEST_UNARY_FP(F32, vf32[0]);
+}
+
+int main(void) {
+  init();
+  test();
+
+  return 0;
+}