Implement directed inlining / BinaryenForceInline

build-js.sh

@@ -768,6 +768,9 @@ export_function "_BinaryenExportGetKind"
 export_function "_BinaryenExportGetName"
 export_function "_BinaryenExportGetValue"
 
+# Utility
+export_function "_BinaryenForceInline"
+
 # 'Relooper' operations
 export_function "_RelooperCreate"
 export_function "_RelooperAddBlock"

src/binaryen-c.cpp

@@ -32,6 +32,7 @@
 #include "wasm2js.h"
 #include "cfg/Relooper.h"
 #include "ir/function-type-utils.h"
+#include "ir/inlining.h"
 #include "ir/utils.h"
 #include "shell-interface.h"
 
@@ -2909,6 +2910,32 @@ BinaryenFunctionTypeRef BinaryenGetFunctionTypeBySignature(BinaryenModuleRef mod
 
   return NULL;
 }
+int BinaryenForceInline(BinaryenModuleRef module, BinaryenFunctionRef funcRef, BinaryenExpressionRef callRef) {
+  if (tracing) {
+    std::cout << "  BinaryenForceInline(theModule, functions[" << functions[funcRef] << "], " << callRef << ");\n";
+  }
+
+  auto* wasm = (Module*)module;
+  auto* func = (Function*)funcRef;
+  auto* call = (Call*)callRef;
+
+  struct Updater : public PostWalker<Updater> {
+    Call* callToReplace;
+    bool callReplaced;
+
+    void visitCall(Call* call) {
+      if (callToReplace == call) {
+        replaceCurrent(doInlining(getModule(), getFunction(), call));
+        callReplaced = true;
+      }
+    }
+  } updater;
+  updater.callToReplace = call;
+  updater.callReplaced = false;
+  updater.walkFunctionInModule(func, wasm);
+  if (updater.callReplaced) UniqueNameMapper::uniquify(func->body);
+  return updater.callReplaced;
+}
 
 #ifdef __EMSCRIPTEN__
 // Override atexit - we don't need any global ctors to actually run, and

src/binaryen-c.h

@@ -950,6 +950,9 @@ void BinaryenSetAPITracing(int on);
 // signature, it returns a pointer to the existing signature or NULL if there is no
 // such signature yet.
 BinaryenFunctionTypeRef BinaryenGetFunctionTypeBySignature(BinaryenModuleRef module, BinaryenType result, BinaryenType* paramTypes, BinaryenIndex numParams);
+// Directs the API to inline a specific call into the caller. Returns `1` if the
+// call has been found in the caller's body and replaced, otherwise `0`.
+int BinaryenForceInline(BinaryenModuleRef module, BinaryenFunctionRef func, BinaryenExpressionRef call);
 
 #ifdef __cplusplus
 } // extern "C"

src/ir/inlining.h

@@ -0,0 +1,80 @@
+/*
+ * Copyright 2019 WebAssembly Community Group participants
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef wasm_ir_inlining_h
+#define wasm_ir_inlining_h
+
+#include "wasm.h"
+#include "wasm-builder.h"
+#include "ir/literal-utils.h"
+
+namespace wasm {
+
+// Core inlining logic. Modifies the caller (adding locals as needed), and returns the inlined code.
+static Expression* doInlining(Module* module, Function* caller, Call* call) {
+  auto* callee = module->getFunction(call->target);
+  Builder builder(*module);
+  auto* block = Builder(*module).makeBlock();
+  block->name = Name(std::string("__inlined_func$") + callee->name.str);
+  // set up a locals mapping
+  struct Updater : public PostWalker<Updater> {
+    std::map<Index, Index> localMapping;
+    Name returnName;
+    Builder* builder;
+
+    void visitReturn(Return* curr) {
+      replaceCurrent(builder->makeBreak(returnName, curr->value));
+    }
+    void visitGetLocal(GetLocal* curr) {
+      curr->index = localMapping[curr->index];
+    }
+    void visitSetLocal(SetLocal* curr) {
+      curr->index = localMapping[curr->index];
+    }
+  } updater;
+  updater.returnName = block->name;
+  updater.builder = &builder;
+  for (Index i = 0; i < callee->getNumLocals(); i++) {
+    updater.localMapping[i] = builder.addVar(caller, callee->getLocalType(i));
+  }
+  // assign the operands into the params
+  for (Index i = 0; i < callee->params.size(); i++) {
+    block->list.push_back(builder.makeSetLocal(updater.localMapping[i], call->operands[i]));
+  }
+  // zero out the vars (as we may be in a loop, and may depend on their zero-init value
+  for (Index i = 0; i < callee->vars.size(); i++) {
+    block->list.push_back(builder.makeSetLocal(updater.localMapping[callee->getVarIndexBase() + i], LiteralUtils::makeZero(callee->vars[i], *module)));
+  }
+  // generate and update the inlined contents
+  auto* contents = ExpressionManipulator::copy(callee->body, *module);
+  updater.walk(contents);
+  block->list.push_back(contents);
+  block->type = call->type;
+  // if the function returned a value, we just set the block containing the
+  // inlined code to have that type. or, if the function was void and
+  // contained void, that is fine too. a bad case is a void function in which
+  // we have unreachable code, so we would be replacing a void call with an
+  // unreachable; we need to handle
+  if (contents->type == unreachable && block->type == none) {
+    // make the block reachable by adding a break to it
+    block->list.push_back(builder.makeBreak(block->name));
+  }
+  return block;
+}
+
+} // namespace wasm
+
+#endif // wasm_ir_inlining_h

src/js/binaryen.js-post.js

@@ -1819,6 +1819,9 @@ function wrapModule(module, self) {
   self['setStart'] = function(start) {
     return Module['_BinaryenSetStart'](module, start);
   };
+  self['forceInline'] = function (func, call) {
+   return Module['_BinaryenForceInline'](module, func, call) == 1;
+  };
   self['emitText'] = function() {
     var old = out;
     var ret = '';

src/passes/Inlining.cpp

@@ -35,6 +35,7 @@
 #include "wasm.h"
 #include "pass.h"
 #include "wasm-builder.h"
+#include "ir/inlining.h"
 #include "ir/literal-utils.h"
 #include "ir/module-utils.h"
 #include "ir/utils.h"
@@ -172,61 +173,6 @@ struct Planner : public WalkerPass<PostWalker<Planner>> {
   InliningState* state;
 };
 
-// Core inlining logic. Modifies the outside function (adding locals as
-// needed), and returns the inlined code.
-static Expression* doInlining(Module* module, Function* into, InliningAction& action) {
-  Function* from = action.contents;
-  auto* call = (*action.callSite)->cast<Call>();
-  Builder builder(*module);
-  auto* block = Builder(*module).makeBlock();
-  block->name = Name(std::string("__inlined_func$") + from->name.str);
-  *action.callSite = block;
-  // set up a locals mapping
-  struct Updater : public PostWalker<Updater> {
-    std::map<Index, Index> localMapping;
-    Name returnName;
-    Builder* builder;
-
-    void visitReturn(Return* curr) {
-      replaceCurrent(builder->makeBreak(returnName, curr->value));
-    }
-    void visitGetLocal(GetLocal* curr) {
-      curr->index = localMapping[curr->index];
-    }
-    void visitSetLocal(SetLocal* curr) {
-      curr->index = localMapping[curr->index];
-    }
-  } updater;
-  updater.returnName = block->name;
-  updater.builder = &builder;
-  for (Index i = 0; i < from->getNumLocals(); i++) {
-    updater.localMapping[i] = builder.addVar(into, from->getLocalType(i));
-  }
-  // assign the operands into the params
-  for (Index i = 0; i < from->params.size(); i++) {
-    block->list.push_back(builder.makeSetLocal(updater.localMapping[i], call->operands[i]));
-  }
-  // zero out the vars (as we may be in a loop, and may depend on their zero-init value
-  for (Index i = 0; i < from->vars.size(); i++) {
-    block->list.push_back(builder.makeSetLocal(updater.localMapping[from->getVarIndexBase() + i], LiteralUtils::makeZero(from->vars[i], *module)));
-  }
-  // generate and update the inlined contents
-  auto* contents = ExpressionManipulator::copy(from->body, *module);
-  updater.walk(contents);
-  block->list.push_back(contents);
-  block->type = call->type;
-  // if the function returned a value, we just set the block containing the
-  // inlined code to have that type. or, if the function was void and
-  // contained void, that is fine too. a bad case is a void function in which
-  // we have unreachable code, so we would be replacing a void call with an
-  // unreachable; we need to handle
-  if (contents->type == unreachable && block->type == none) {
-    // make the block reachable by adding a break to it
-    block->list.push_back(builder.makeBreak(block->name));
-  }
-  return block;
-}
-
 struct Inlining : public Pass {
   // whether to optimize where we inline
   bool optimize = false;
@@ -320,7 +266,8 @@ struct Inlining : public Pass {
 #ifdef INLINING_DEBUG
         std::cout << "inline " << inlinedName << " into " << func->name << '\n';
 #endif
-        doInlining(module, func.get(), action);
+        *action.callSite = doInlining(module, func.get(), (*action.callSite)->cast<Call>());
+
         inlinedUses[inlinedName]++;
         inlinedInto.insert(func.get());
         assert(inlinedUses[inlinedName] <= infos[inlinedName].calls);

test/binaryen.js/inlining.js

@@ -0,0 +1,24 @@
+var module = new Binaryen.Module();
+var signature = module.addFunctionType("i", Binaryen.i32, []);
+
+var theCall;
+
+var outer = module.addFunction("outer", signature, [],
+  theCall = module.call("inner", [], Binaryen.i32),
+);
+
+var inner = module.addFunction("inner", signature, [],
+  module.i32.const(42)
+);
+
+console.log("=== before ===");
+module.validate();
+console.log(module.emitText());
+
+if (module.forceInline(outer, theCall)) {
+  module.removeFunction("inner");
+}
+
+console.log("=== after ===");
+module.validate();
+console.log(module.emitText());

test/binaryen.js/inlining.js.txt

@@ -0,0 +1,21 @@
+=== before ===
+(module
+ (type $i (func (result i32)))
+ (func $outer (; 0 ;) (type $i) (result i32)
+  (call $inner)
+ )
+ (func $inner (; 1 ;) (type $i) (result i32)
+  (i32.const 42)
+ )
+)
+
+=== after ===
+(module
+ (type $i (func (result i32)))
+ (func $outer (; 0 ;) (type $i) (result i32)
+  (block $__inlined_func$inner (result i32)
+   (i32.const 42)
+  )
+ )
+)
+