Run tests on AppVeyor (#385)

Fixes issue #326.

* Install target installs all executables; this is required because we don't
  actually know where MSVC builds its targets to
* Use absolute paths when running all executables
* Set `PYTHONPATH` to test directory; for some reason the Windows `sys.path`
  doesn't include the current script's directory
* In `wasmdump`, strip the directory up to the last slash or backslash
* In `wasm-interp`, Use round-to-nearest-ties-to-even when converting from
  uint64 to float or double
* Check for backslash or slash in `get_dirname` in `wasm-interp`, when looking
  for modules alongside the JSON file
* print floats in `wasm-interp` using `%f` not `%g`, since MSVC prints using 3
  digits for exponent instead of 2
* In `run-wasm-link.py`, remove file before renaming on top of it

4 files changed, 55 insertions, 11 deletions

diff --git a/src/binary-reader-objdump.cc b/src/binary-reader-objdump.cc
index c6698289..3e117728 100644
--- a/src/binary-reader-objdump.cc
+++ b/src/binary-reader-objdump.cc
@@ -21,6 +21,7 @@
 #include <string.h>
 #include <stdio.h>
 
+#include <algorithm>
 #include <vector>
 
 #include "binary-reader-nop.h"
@@ -327,11 +328,18 @@ Result BinaryReaderObjdump::OnCount(uint32_t count) {
 
 Result BinaryReaderObjdump::BeginModule(uint32_t version) {
   if (options->print_header) {
-    const char* basename = strrchr(options->infile, '/');
-    if (basename)
-      basename++;
-    else
+    const char* last_slash = strrchr(options->infile, '/');
+    const char* last_backslash = strrchr(options->infile, '\\');
+    const char* basename;
+    if (last_slash && last_backslash) {
+      basename = std::max(last_slash, last_backslash) + 1;
+    } else if (last_slash) {
+      basename = last_slash + 1;
+    } else if (last_backslash) {
+      basename = last_backslash + 1;
+    } else {
       basename = options->infile;
+    }
     printf("%s:\tfile format wasm %#08x\n", basename, version);
     header_printed = true;
   }
diff --git a/src/config.h.in b/src/config.h.in
index 453e7985..052aae88 100644
--- a/src/config.h.in
+++ b/src/config.h.in
@@ -265,4 +265,35 @@ typedef int ssize_t;
 #endif
 #endif
 
+#if COMPILER_IS_MSVC && defined(_M_X64)
+// MSVC on x64 generates uint64 -> float conversions but doesn't do
+// round-to-nearest-ties-to-even, which is required by WebAssembly.
+#include <emmintrin.h>
+__inline double wabt_convert_uint64_to_double(unsigned __int64 x) {
+  __m128d result = _mm_setzero_pd();
+  if (x & 0x8000000000000000ULL) {
+    result = _mm_cvtsi64_sd(result, (x >> 1) | (x & 1));
+    result = _mm_add_sd(result, result);
+  } else {
+    result = _mm_cvtsi64_sd(result, x);
+  }
+  return _mm_cvtsd_f64(result);
+}
+
+__inline float wabt_convert_uint64_to_float(unsigned __int64 x) {
+  __m128 result = _mm_setzero_ps();
+  if (x & 0x8000000000000000ULL) {
+    result = _mm_cvtsi64_ss(result, (x >> 1) | (x & 1));
+    result = _mm_add_ss(result, result);
+  } else {
+    result = _mm_cvtsi64_ss(result, x);
+  }
+  return _mm_cvtss_f32(result);
+}
+
+#else
+#define wabt_convert_uint64_to_double(x) static_cast<double>(x)
+#define wabt_convert_uint64_to_float(x) static_cast<float>(x)
+#endif
+
 #endif /* WABT_CONFIG_H_ */
diff --git a/src/interpreter.cc b/src/interpreter.cc
index bb1e6a9c..1e12d4a8 100644
--- a/src/interpreter.cc
+++ b/src/interpreter.cc
@@ -1558,7 +1558,7 @@ InterpreterResult run_interpreter(InterpreterThread* thread,
 
       case InterpreterOpcode::F32ConvertUI64: {
         VALUE_TYPE_I64 value = POP_I64();
-        PUSH_F32(BITCAST_FROM_F32(static_cast<float>(value)));
+        PUSH_F32(BITCAST_FROM_F32(wabt_convert_uint64_to_float(value)));
         break;
       }
 
@@ -1610,7 +1610,7 @@ InterpreterResult run_interpreter(InterpreterThread* thread,
 
       case InterpreterOpcode::F64ConvertUI64: {
         VALUE_TYPE_I64 value = POP_I64();
-        PUSH_F64(BITCAST_FROM_F64(static_cast<double>(value)));
+        PUSH_F64(BITCAST_FROM_F64(wabt_convert_uint64_to_double(value)));
         break;
       }
 
diff --git a/src/tools/wasm-interp.cc b/src/tools/wasm-interp.cc
index 924c6b20..643fc3fa 100644
--- a/src/tools/wasm-interp.cc
+++ b/src/tools/wasm-interp.cc
@@ -19,6 +19,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 
+#include <algorithm>
 #include <vector>
 
 #include "binary-reader.h"
@@ -179,19 +180,23 @@ static void parse_options(int argc, char** argv) {
 }
 
 static StringSlice get_dirname(const char* s) {
-  /* strip everything after and including the last slash, e.g.:
+  /* strip everything after and including the last slash (or backslash), e.g.:
    *
    * s = "foo/bar/baz", => "foo/bar"
    * s = "/usr/local/include/stdio.h", => "/usr/local/include"
    * s = "foo.bar", => ""
+   * s = "some\windows\directory", => "some\windows"
    */
   const char* last_slash = strrchr(s, '/');
-  if (last_slash == nullptr)
+  const char* last_backslash = strrchr(s, '\\');
+  if (!last_slash)
     last_slash = s;
+  if (!last_backslash)
+    last_backslash = s;
 
   StringSlice result;
   result.start = s;
-  result.length = last_slash - s;
+  result.length = std::max(last_slash, last_backslash) - s;
   return result;
 }
 
@@ -213,14 +218,14 @@ static void sprint_typed_value(char* buffer,
     case Type::F32: {
       float value;
       memcpy(&value, &tv->value.f32_bits, sizeof(float));
-      snprintf(buffer, size, "f32:%g", value);
+      snprintf(buffer, size, "f32:%f", value);
       break;
     }
 
     case Type::F64: {
       double value;
       memcpy(&value, &tv->value.f64_bits, sizeof(double));
-      snprintf(buffer, size, "f64:%g", value);
+      snprintf(buffer, size, "f64:%f", value);
       break;
     }