Add BinaryenConstGetValueV128 to C/JS-API (#1931)

This PR adds

void BinaryenConstGetValueV128(BinaryenExpressionRef expr, uint8_t* out);

to the C-API and uses it in Binaryen.getExpressionInfo in the JS-API.

3 files changed, 80 insertions, 33 deletions

diff --git a/src/binaryen-c.cpp b/src/binaryen-c.cpp
index c554b0a23..71cd92da4 100644
--- a/src/binaryen-c.cpp
+++ b/src/binaryen-c.cpp
@@ -1616,6 +1616,15 @@ double BinaryenConstGetValueF64(BinaryenExpressionRef expr) {
   assert(expression->is<Const>());
   return static_cast<Const*>(expression)->value.getf64();
 }
+void BinaryenConstGetValueV128(BinaryenExpressionRef expr, uint8_t* out) {
+  if (tracing) {
+    std::cout << "  BinaryenConstGetValueV128(expressions[" << expressions[expr] << "], " << out << ");\n";
+  }
+
+  auto* expression = (Expression*)expr;
+  assert(expression->is<Const>());
+  memcpy(out, static_cast<Const*>(expression)->value.getv128().data(), 16);
+}
 // Unary
 BinaryenOp BinaryenUnaryGetOp(BinaryenExpressionRef expr) {
   if (tracing) {
@@ -1945,7 +1954,7 @@ BinaryenExpressionRef BinaryenSIMDShuffleGetRight(BinaryenExpressionRef expr) {
 }
 void BinaryenSIMDShuffleGetMask(BinaryenExpressionRef expr, uint8_t *mask) {
   if (tracing) {
-    std::cout << "  BinaryenSIMDShuffleGetMask(expressions[" << expressions[expr] << "]);\n";
+    std::cout << "  BinaryenSIMDShuffleGetMask(expressions[" << expressions[expr] << "], " << mask << ");\n";
   }
 
   auto* expression = (Expression*)expr;
@@ -3067,6 +3076,12 @@ size_t BinaryenSizeofLiteral(void) {
   return sizeof(Literal);
 }
 
+// Returns the size of an allocate and write result object.
+EMSCRIPTEN_KEEPALIVE
+size_t BinaryenSizeofAllocateAndWriteResult(void) {
+  return sizeof(BinaryenModuleAllocateAndWriteResult);
+}
+
 #endif
 
 } // extern "C"
diff --git a/src/binaryen-c.h b/src/binaryen-c.h
index 5355ceeeb..787bfb242 100644
--- a/src/binaryen-c.h
+++ b/src/binaryen-c.h
@@ -618,6 +618,7 @@ int32_t BinaryenConstGetValueI64Low(BinaryenExpressionRef expr);
 int32_t BinaryenConstGetValueI64High(BinaryenExpressionRef expr);
 float BinaryenConstGetValueF32(BinaryenExpressionRef expr);
 double BinaryenConstGetValueF64(BinaryenExpressionRef expr);
+void BinaryenConstGetValueV128(BinaryenExpressionRef expr, uint8_t* out);
 
 BinaryenOp BinaryenUnaryGetOp(BinaryenExpressionRef expr);
 BinaryenExpressionRef BinaryenUnaryGetValue(BinaryenExpressionRef expr);
diff --git a/src/js/binaryen.js-post.js b/src/js/binaryen.js-post.js
index 1eef5757e..aee41255c 100644
--- a/src/js/binaryen.js-post.js
+++ b/src/js/binaryen.js-post.js
@@ -365,6 +365,13 @@ Module['ConvertUVecI32x4ToVecF32x4'] = Module['_BinaryenConvertUVecI32x4ToVecF32
 Module['ConvertSVecI64x2ToVecF64x2'] = Module['_BinaryenConvertSVecI64x2ToVecF64x2']();
 Module['ConvertUVecI64x2ToVecF64x2'] = Module['_BinaryenConvertUVecI64x2ToVecF64x2']();
 
+// The size of a single literal in memory as used in Const creation,
+// which is a little different: we don't want users to need to make
+// their own Literals, as the C API handles them by value, which means
+// we would leak them. Instead, Const creation is fused together with
+// an intermediate stack allocation of this size to pass the value.
+var sizeOfLiteral = _BinaryenSizeofLiteral();
+
 // 'Module' interface
 Module['Module'] = function(module) {
   assert(!module); // guard against incorrect old API usage
@@ -482,13 +489,6 @@ function wrapModule(module, self) {
     }
   }
 
-  // The Const creation API is a little different: we don't want users to
-  // need to make their own Literals, as the C API handles them by value,
-  // which means we would leak them. Instead, this is the only API that
-  // accepts Literals, so fuse it with Literal creation
-  var temp = _malloc(Module['_BinaryenSizeofLiteral']()); // a single literal in memory. the LLVM C ABI
-                                                          // makes us pass pointers to this.
-
   self['i32'] = {
     'load': function(offset, align, ptr) {
       return Module['_BinaryenLoad'](module, 4, true, offset, align, Module['i32'], ptr);
@@ -515,8 +515,11 @@ function wrapModule(module, self) {
       return Module['_BinaryenStore'](module, 2, offset, align, ptr, value, Module['i32']);
     },
     'const': function(x) {
-      Module['_BinaryenLiteralInt32'](temp, x);
-      return Module['_BinaryenConst'](module, temp);
+      return preserveStack(function() {
+        var tempLiteral = stackAlloc(sizeOfLiteral);
+        Module['_BinaryenLiteralInt32'](tempLiteral, x);
+        return Module['_BinaryenConst'](module, tempLiteral);
+      });
     },
     'clz': function(value) {
       return Module['_BinaryenUnary'](module, Module['ClzInt32'], value);
@@ -778,8 +781,11 @@ function wrapModule(module, self) {
       return Module['_BinaryenStore'](module, 4, offset, align, ptr, value, Module['i64']);
     },
     'const': function(x, y) {
-      Module['_BinaryenLiteralInt64'](temp, x, y);
-      return Module['_BinaryenConst'](module, temp);
+      return preserveStack(function() {
+        var tempLiteral = stackAlloc(sizeOfLiteral);
+        Module['_BinaryenLiteralInt64'](tempLiteral, x, y);
+        return Module['_BinaryenConst'](module, tempLiteral);
+      });
     },
     'clz': function(value) {
       return Module['_BinaryenUnary'](module, Module['ClzInt64'], value);
@@ -1049,12 +1055,18 @@ function wrapModule(module, self) {
       return Module['_BinaryenStore'](module, 4, offset, align, ptr, value, Module['f32']);
     },
     'const': function(x) {
-      Module['_BinaryenLiteralFloat32'](temp, x);
-      return Module['_BinaryenConst'](module, temp);
+      return preserveStack(function() {
+        var tempLiteral = stackAlloc(sizeOfLiteral);
+        Module['_BinaryenLiteralFloat32'](tempLiteral, x);
+        return Module['_BinaryenConst'](module, tempLiteral);
+      });
     },
     'const_bits': function(x) {
-      Module['_BinaryenLiteralFloat32Bits'](temp, x);
-      return Module['_BinaryenConst'](module, temp);
+      return preserveStack(function() {
+        var tempLiteral = stackAlloc(sizeOfLiteral);
+        Module['_BinaryenLiteralFloat32Bits'](tempLiteral, x);
+        return Module['_BinaryenConst'](module, tempLiteral);
+      });
     },
     'neg': function(value) {
       return Module['_BinaryenUnary'](module, Module['NegFloat32'], value);
@@ -1148,12 +1160,18 @@ function wrapModule(module, self) {
       return Module['_BinaryenStore'](module, 8, offset, align, ptr, value, Module['f64']);
     },
     'const': function(x) {
-      Module['_BinaryenLiteralFloat64'](temp, x);
-      return Module['_BinaryenConst'](module, temp);
+      return preserveStack(function() {
+        var tempLiteral = stackAlloc(sizeOfLiteral);
+        Module['_BinaryenLiteralFloat64'](tempLiteral, x);
+        return Module['_BinaryenConst'](module, tempLiteral);
+      });
     },
     'const_bits': function(x, y) {
-      Module['_BinaryenLiteralFloat64Bits'](temp, x, y);
-      return Module['_BinaryenConst'](module, temp);
+      return preserveStack(function() {
+        var tempLiteral = stackAlloc(sizeOfLiteral);
+        Module['_BinaryenLiteralFloat64Bits'](tempLiteral, x, y);
+        return Module['_BinaryenConst'](module, tempLiteral);
+      });
     },
     'neg': function(value) {
       return Module['_BinaryenUnary'](module, Module['NegFloat64'], value);
@@ -1248,8 +1266,9 @@ function wrapModule(module, self) {
     },
     'const': function(i8s) {
       return preserveStack(function() {
-        Module['_BinaryenLiteralVec128'](temp, i8sToStack(i8s));
-        return Module['_BinaryenConst'](module, temp);
+        var tempLiteral = stackAlloc(sizeOfLiteral);
+        Module['_BinaryenLiteralVec128'](tempLiteral, i8sToStack(i8s));
+        return Module['_BinaryenConst'](module, tempLiteral);
       });
     },
     'not': function(value) {
@@ -1729,7 +1748,7 @@ function wrapModule(module, self) {
     });
   };
   self['removeFunctionType'] = function(name) {
-    return preserveStack(function () {
+    return preserveStack(function() {
       return Module['_BinaryenRemoveFunctionType'](module, strToStack(name));
     });
   };
@@ -1754,7 +1773,7 @@ function wrapModule(module, self) {
     });
   }
   self['removeGlobal'] = function(name) {
-    return preserveStack(function () {
+    return preserveStack(function() {
       return Module['_BinaryenRemoveGlobal'](module, strToStack(name));
     });
   }
@@ -1900,10 +1919,11 @@ function wrapModule(module, self) {
   };
   self['emitBinary'] = function(sourceMapUrl) {
     return preserveStack(function() {
-      Module['_BinaryenModuleAllocateAndWrite'](temp, module, strToStack(sourceMapUrl));
-      var binaryPtr    = HEAPU32[ temp >>> 2     ];
-      var binaryBytes  = HEAPU32[(temp >>> 2) + 1];
-      var sourceMapPtr = HEAPU32[(temp >>> 2) + 2];
+      var tempBuffer = stackAlloc(_BinaryenSizeofAllocateAndWriteResult());
+      Module['_BinaryenModuleAllocateAndWrite'](tempBuffer, module, strToStack(sourceMapUrl));
+      var binaryPtr    = HEAPU32[ tempBuffer >>> 2     ];
+      var binaryBytes  = HEAPU32[(tempBuffer >>> 2) + 1];
+      var sourceMapPtr = HEAPU32[(tempBuffer >>> 2) + 2];
       try {
         var buffer = new Uint8Array(binaryBytes);
         buffer.set(HEAPU8.subarray(binaryPtr, binaryPtr + binaryBytes));
@@ -2090,7 +2110,18 @@ Module['getExpressionInfo'] = function(expr) {
         case Module['i32']: value = Module['_BinaryenConstGetValueI32'](expr); break;
         case Module['i64']: value = { 'low': Module['_BinaryenConstGetValueI64Low'](expr), 'high': Module['_BinaryenConstGetValueI64High'](expr) }; break;
         case Module['f32']: value = Module['_BinaryenConstGetValueF32'](expr); break;
-        case Module['f64']: value =  Module['_BinaryenConstGetValueF64'](expr); break;
+        case Module['f64']: value = Module['_BinaryenConstGetValueF64'](expr); break;
+        case Module['v128']: {
+          preserveStack(function() {
+            var tempBuffer = stackAlloc(16);
+            Module['_BinaryenConstGetValueV128'](expr, tempBuffer);
+            value = new Array(16);
+            for (var i = 0 ; i < 16; i++) {
+              value[i] = HEAPU8[tempBuffer + i];
+            }
+          });
+          break;
+        }
         default: throw Error('unexpected type: ' + type);
       }
       return {
@@ -2203,11 +2234,11 @@ Module['getExpressionInfo'] = function(expr) {
       };
     case Module['SIMDShuffleId']:
       return preserveStack(function() {
-        var ret = stackAlloc(16);
-        Module['_BinaryenSIMDShuffleGetMask'](expr, ret);
-        var mask = [];
+        var tempBuffer = stackAlloc(16);
+        Module['_BinaryenSIMDShuffleGetMask'](expr, tempBuffer);
+        var mask = new Array(16);
         for (var i = 0 ; i < 16; i++) {
-          mask[i] = HEAP8[ret + i];
+          mask[i] = HEAPU8[tempBuffer + i];
         }
         return {
           'id': id,