[wasm] Int64Lowering of Word64Popcnt.

test/cctest/wasm/test-run-wasm-64.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
 
 #include "src/wasm/wasm-macro-gen.h"
 
@@ skipping 244 matching lines @@
   BUILD(r, WASM_I64_UCONVERT_I32(WASM_GET_LOCAL(0)));
   FOR_UINT32_INPUTS(i) { CHECK_EQ(static_cast<uint64_t>(*i), r.Call(*i)); }
 }
 
 // kExprF64ReinterpretI64:
 // kExprI64ReinterpretF64:
 
 // kExprI64Clz:
 // kExprI64Ctz:
 // kExprI64Popcnt:
+TEST(Run_WasmI64Popcnt) {
+  struct {
+    int64_t expected;
+    uint64_t input;
+  } values[] = {{64, 0xffffffffffffffff},
+                {0, 0x0000000000000000},
+                {2, 0x0000080000008000},
+                {26, 0x1123456782345678},
+                {38, 0xffedcba09edcba09}};
+
+  WasmRunner<int64_t> r(MachineType::Uint64());
+  BUILD(r, WASM_I64_POPCNT(WASM_GET_LOCAL(0)));
+  for (size_t i = 0; i < arraysize(values); i++) {
+    CHECK_EQ(values[i].expected, r.Call(values[i].input));
+  }
+}
 
 // kExprF32SConvertI64:
 TEST(Run_WasmF32SConvertI64) {
   WasmRunner<float> r(MachineType::Int64());
   BUILD(r, WASM_F32_SCONVERT_I64(WASM_GET_LOCAL(0)));
   FOR_INT64_INPUTS(i) { CHECK_EQ(static_cast<float>(*i), r.Call(*i)); }
 }
 // kExprF32UConvertI64:
 TEST(Run_WasmF32UConvertI64) {
   struct {
@@ skipping 208 matching lines @@
             WASM_I64V_10(0xbcd1234000000013), WASM_I64V_10(0xbcd1234000000014),
             WASM_I64V_10(0xbcd1234000000015), WASM_I64V_10(0xbcd1234000000016),
             WASM_I64V_10(0xbcd1234000000017), WASM_I64V_10(0xbcd1234000000018),
             WASM_I64V_10(0xbcd1234000000019), WASM_I64V_10(0xbcd123400000001a),
             WASM_I64V_10(0xbcd123400000001b), WASM_I64V_10(0xbcd123400000001c),
             WASM_I64V_10(0xbcd123400000001d))));
 
     CHECK_EQ(i + 0xb, r.Call());
   }
 }