Simplify asmConst handling. NFC. (#3558)

Support for multiple signatures per JS code string was removed in #2422.

emscripten now only needs to know that address and the body of the JS
function.

See https://github.com/emscripten-core/emscripten/pull/13452.

8 files changed, 28 insertions, 95 deletions

diff --git a/src/wasm/wasm-emscripten.cpp b/src/wasm/wasm-emscripten.cpp
index 0aabcc0b4..24fb7bcdc 100644
--- a/src/wasm/wasm-emscripten.cpp
+++ b/src/wasm/wasm-emscripten.cpp
@@ -188,38 +188,17 @@ private:
   std::vector<Address> segmentOffsets; // segment index => address offset
 };
 
-enum class Proxying {
-  None,
-  Sync,
-  Async,
-};
-
-std::string proxyingSuffix(Proxying proxy) {
-  switch (proxy) {
-    case Proxying::None:
-      return "";
-    case Proxying::Sync:
-      return "sync_on_main_thread_";
-    case Proxying::Async:
-      return "async_on_main_thread_";
-  }
-  WASM_UNREACHABLE("invalid prozy type");
-}
-
 struct AsmConstWalker : public LinearExecutionWalker<AsmConstWalker> {
   Module& wasm;
   bool minimizeWasmChanges;
   StringConstantTracker stringTracker;
 
   struct AsmConst {
-    std::set<Signature> sigs;
     Address id;
     std::string code;
-    Proxying proxy;
   };
 
   std::vector<AsmConst> asmConsts;
-  std::set<std::pair<Signature, Proxying>> allSigs;
   // last sets in the current basic block, per index
   std::map<Index, LocalSet*> sets;
 
@@ -235,11 +214,8 @@ struct AsmConstWalker : public LinearExecutionWalker<AsmConstWalker> {
   void process();
 
 private:
-  void createAsmConst(uint64_t id, std::string code, Signature sig, Name name);
-  Signature asmConstSig(Signature baseSig);
-  Name nameForImportWithSig(Signature sig, Proxying proxy);
+  void createAsmConst(uint64_t id, std::string code);
   void addImports();
-  Proxying proxyType(Name name);
 
   std::vector<std::unique_ptr<Function>> queuedImports;
 };
@@ -263,8 +239,6 @@ void AsmConstWalker::visitCall(Call* curr) {
     return;
   }
 
-  auto baseSig = wasm.getFunction(curr->target)->sig;
-  auto sig = asmConstSig(baseSig);
   auto* arg = curr->operands[0];
   while (!arg->dynCast<Const>()) {
     if (auto* get = arg->dynCast<LocalGet>()) {
@@ -320,16 +294,7 @@ void AsmConstWalker::visitCall(Call* curr) {
   auto* value = arg->cast<Const>();
   int64_t address = value->value.getInteger();
   auto code = stringTracker.codeForConstAddr(address);
-  createAsmConst(address, code, sig, importName);
-}
-
-Proxying AsmConstWalker::proxyType(Name name) {
-  if (name.hasSubstring("_sync_on_main_thread")) {
-    return Proxying::Sync;
-  } else if (name.hasSubstring("_async_on_main_thread")) {
-    return Proxying::Async;
-  }
-  return Proxying::None;
+  createAsmConst(address, code);
 }
 
 void AsmConstWalker::process() {
@@ -340,35 +305,21 @@ void AsmConstWalker::process() {
   addImports();
 }
 
-void AsmConstWalker::createAsmConst(uint64_t id,
-                                    std::string code,
-                                    Signature sig,
-                                    Name name) {
+void AsmConstWalker::createAsmConst(uint64_t id, std::string code) {
   AsmConst asmConst;
   asmConst.id = id;
   asmConst.code = code;
-  asmConst.sigs.insert(sig);
-  asmConst.proxy = proxyType(name);
   asmConsts.push_back(asmConst);
 }
 
-Signature AsmConstWalker::asmConstSig(Signature baseSig) {
-  assert(baseSig.params.size() >= 1);
-  // Omit the signature of the "code" parameter, taken as a string, as the
-  // first argument
-  return Signature(
-    Type(std::vector<Type>(baseSig.params.begin() + 1, baseSig.params.end())),
-    baseSig.results);
-}
-
 void AsmConstWalker::addImports() {
   for (auto& import : queuedImports) {
     wasm.addFunction(import.release());
   }
 }
 
-static AsmConstWalker fixEmAsmConstsAndReturnWalker(Module& wasm,
-                                                    bool minimizeWasmChanges) {
+static AsmConstWalker findEmAsmConstsAndReturnWalker(Module& wasm,
+                                                     bool minimizeWasmChanges) {
   AsmConstWalker walker(wasm, minimizeWasmChanges);
   walker.process();
   return walker;
@@ -407,7 +358,7 @@ struct EmJsWalker : public PostWalker<EmJsWalker> {
   }
 };
 
-EmJsWalker fixEmJsFuncsAndReturnWalker(Module& wasm) {
+EmJsWalker findEmJsFuncsAndReturnWalker(Module& wasm) {
   EmJsWalker walker(wasm);
   walker.walkModule(&wasm);
 
@@ -418,20 +369,6 @@ EmJsWalker fixEmJsFuncsAndReturnWalker(Module& wasm) {
   return walker;
 }
 
-void printSignatures(std::ostream& o, const std::set<Signature>& c) {
-  o << "[";
-  bool first = true;
-  for (auto& sig : c) {
-    if (first) {
-      first = false;
-    } else {
-      o << ",";
-    }
-    o << '"' << getSig(sig.results, sig.params) << '"';
-  }
-  o << "]";
-}
-
 std::string EmscriptenGlueGenerator::generateEmscriptenMetadata() {
   bool commaFirst;
   auto nextElement = [&commaFirst]() {
@@ -447,7 +384,7 @@ std::string EmscriptenGlueGenerator::generateEmscriptenMetadata() {
   meta << "{\n";
 
   AsmConstWalker emAsmWalker =
-    fixEmAsmConstsAndReturnWalker(wasm, minimizeWasmChanges);
+    findEmAsmConstsAndReturnWalker(wasm, minimizeWasmChanges);
 
   // print
   commaFirst = true;
@@ -455,16 +392,12 @@ std::string EmscriptenGlueGenerator::generateEmscriptenMetadata() {
     meta << "  \"asmConsts\": {";
     for (auto& asmConst : emAsmWalker.asmConsts) {
       meta << nextElement();
-      meta << '"' << asmConst.id << "\": [\"" << asmConst.code << "\", ";
-      printSignatures(meta, asmConst.sigs);
-      meta << ", [\"" << proxyingSuffix(asmConst.proxy) << "\"]";
-
-      meta << "]";
+      meta << '"' << asmConst.id << "\": \"" << asmConst.code << "\"";
     }
     meta << "\n  },\n";
   }
 
-  EmJsWalker emJsWalker = fixEmJsFuncsAndReturnWalker(wasm);
+  EmJsWalker emJsWalker = findEmJsFuncsAndReturnWalker(wasm);
   if (!emJsWalker.codeByName.empty()) {
     meta << "  \"emJsFuncs\": {";
     commaFirst = true;
diff --git a/test/lit/wasm-emscripten-finalize/passive-pic.wat b/test/lit/wasm-emscripten-finalize/passive-pic.wat
index e9af5b1d9..14e6842a3 100644
--- a/test/lit/wasm-emscripten-finalize/passive-pic.wat
+++ b/test/lit/wasm-emscripten-finalize/passive-pic.wat
@@ -4,7 +4,7 @@
 ;; RUN: wasm-emscripten-finalize --enable-bulk-memory %s -o out.wasm | filecheck %s
 
 ;; CHECK:  "asmConsts": {
-;; CHECK:    "3": ["hello", ["iii"], [""]]
+;; CHECK:    "3": "hello"
 ;; CHECK:  },
 
 (module
diff --git a/test/lld/em_asm.wat.mem.out b/test/lld/em_asm.wat.mem.out
index 8a24bb270..ca85963ad 100644
--- a/test/lld/em_asm.wat.mem.out
+++ b/test/lld/em_asm.wat.mem.out
@@ -68,9 +68,9 @@
 --BEGIN METADATA --
 {
   "asmConsts": {
-    "568": ["{ Module.print(\"Hello world\"); }", ["iii"], [""]],
-    "602": ["{ return $0 + $1; }", ["iii"], [""]],
-    "625": ["{ Module.print(\"Got \" + $0); }", ["iii"], [""]]
+    "568": "{ Module.print(\"Hello world\"); }",
+    "602": "{ return $0 + $1; }",
+    "625": "{ Module.print(\"Got \" + $0); }"
   },
   "tableSize": 1,
   "declares": [
diff --git a/test/lld/em_asm.wat.out b/test/lld/em_asm.wat.out
index f7655985c..487f51c14 100644
--- a/test/lld/em_asm.wat.out
+++ b/test/lld/em_asm.wat.out
@@ -69,9 +69,9 @@
 --BEGIN METADATA --
 {
   "asmConsts": {
-    "568": ["{ Module.print(\"Hello world\"); }", ["iii"], [""]],
-    "602": ["{ return $0 + $1; }", ["iii"], [""]],
-    "625": ["{ Module.print(\"Got \" + $0); }", ["iii"], [""]]
+    "568": "{ Module.print(\"Hello world\"); }",
+    "602": "{ return $0 + $1; }",
+    "625": "{ Module.print(\"Got \" + $0); }"
   },
   "tableSize": 1,
   "declares": [
diff --git a/test/lld/em_asm64.wat.out b/test/lld/em_asm64.wat.out
index 35425a600..13a279cd4 100644
--- a/test/lld/em_asm64.wat.out
+++ b/test/lld/em_asm64.wat.out
@@ -69,9 +69,9 @@
 --BEGIN METADATA --
 {
   "asmConsts": {
-    "568": ["{ Module.print(\"Hello world\"); }", ["ijj"], [""]],
-    "602": ["{ return $0 + $1; }", ["ijj"], [""]],
-    "625": ["{ Module.print(\"Got \" + $0); }", ["ijj"], [""]]
+    "568": "{ Module.print(\"Hello world\"); }",
+    "602": "{ return $0 + $1; }",
+    "625": "{ Module.print(\"Got \" + $0); }"
   },
   "tableSize": 1,
   "declares": [
diff --git a/test/lld/em_asm_O0.wat.out b/test/lld/em_asm_O0.wat.out
index 48c9158bc..be664978c 100644
--- a/test/lld/em_asm_O0.wat.out
+++ b/test/lld/em_asm_O0.wat.out
@@ -94,9 +94,9 @@
 --BEGIN METADATA --
 {
   "asmConsts": {
-    "568": ["{ Module.print(\"Hello world\"); }", ["iii"], [""]],
-    "601": ["{ return $0 + $1; }", ["iii"], [""]],
-    "621": ["{ Module.print(\"Got \" + $0); }", ["iii"], [""]]
+    "568": "{ Module.print(\"Hello world\"); }",
+    "601": "{ return $0 + $1; }",
+    "621": "{ Module.print(\"Got \" + $0); }"
   },
   "tableSize": 1,
   "declares": [
diff --git a/test/lld/em_asm_main_thread.wat.out b/test/lld/em_asm_main_thread.wat.out
index 55e992a22..9609cef56 100644
--- a/test/lld/em_asm_main_thread.wat.out
+++ b/test/lld/em_asm_main_thread.wat.out
@@ -194,9 +194,9 @@
 --BEGIN METADATA --
 {
   "asmConsts": {
-    "568": ["{ Module.print(\"Hello world\"); }", ["iii"], ["sync_on_main_thread_"]],
-    "601": ["{ return $0 + $1; }", ["iii"], ["sync_on_main_thread_"]],
-    "621": ["{ Module.print(\"Got \" + $0); }", ["iii"], ["sync_on_main_thread_"]]
+    "568": "{ Module.print(\"Hello world\"); }",
+    "601": "{ return $0 + $1; }",
+    "621": "{ Module.print(\"Got \" + $0); }"
   },
   "tableSize": 1,
   "declares": [
diff --git a/test/lld/em_asm_shared.wat.out b/test/lld/em_asm_shared.wat.out
index c9872a503..fd143a016 100644
--- a/test/lld/em_asm_shared.wat.out
+++ b/test/lld/em_asm_shared.wat.out
@@ -95,9 +95,9 @@
 --BEGIN METADATA --
 {
   "asmConsts": {
-    "0": ["{ Module.print(\"Hello world\"); }", ["iii"], [""]],
-    "34": ["{ return $0 + $1; }", ["iii"], [""]],
-    "57": ["{ Module.print(\"Got \" + $0); }", ["iii"], [""]]
+    "0": "{ Module.print(\"Hello world\"); }",
+    "34": "{ return $0 + $1; }",
+    "57": "{ Module.print(\"Got \" + $0); }"
   },
   "tableSize": 0,
   "declares": [