[WebAssembly] Define call-indirect-overlong and bulk-memory-opt features (#117087)

This defines some new target features. These are subsets of existing
features that reflect implementation concerns:

- "call-indirect-overlong" - implied by "reference-types"; just the
overlong encoding for the `call_indirect` immediate, and not the actual
reference types.

- "bulk-memory-opt" - implied by "bulk-memory": just `memory.copy` and
`memory.fill`, and not the other instructions in the bulk-memory
proposal.

This is split out from https://github.com/llvm/llvm-project/pull/112035.

---------

Co-authored-by: Heejin Ahn <aheejin@gmail.com>

1 files changed, 34 insertions, 0 deletions

diff --git a/clang/lib/Basic/Targets/WebAssembly.cpp b/clang/lib/Basic/Targets/WebAssembly.cpp
index 0b380bd..d9d01bc 100644
--- a/clang/lib/Basic/Targets/WebAssembly.cpp
+++ b/clang/lib/Basic/Targets/WebAssembly.cpp
@@ -47,6 +47,8 @@ bool WebAssemblyTargetInfo::hasFeature(StringRef Feature) const {
   return llvm::StringSwitch<bool>(Feature)
       .Case("atomics", HasAtomics)
       .Case("bulk-memory", HasBulkMemory)
+      .Case("bulk-memory-opt", HasBulkMemoryOpt)
+      .Case("call-indirect-overlong", HasCallIndirectOverlong)
       .Case("exception-handling", HasExceptionHandling)
       .Case("extended-const", HasExtendedConst)
       .Case("fp16", HasFP16)
@@ -79,6 +81,8 @@ void WebAssemblyTargetInfo::getTargetDefines(const LangOptions &Opts,
     Builder.defineMacro("__wasm_atomics__");
   if (HasBulkMemory)
     Builder.defineMacro("__wasm_bulk_memory__");
+  if (HasBulkMemoryOpt)
+    Builder.defineMacro("__wasm_bulk_memory_opt__");
   if (HasExceptionHandling)
     Builder.defineMacro("__wasm_exception_handling__");
   if (HasExtendedConst)
@@ -155,6 +159,8 @@ bool WebAssemblyTargetInfo::initFeatureMap(
     const std::vector<std::string> &FeaturesVec) const {
   auto addGenericFeatures = [&]() {
     Features["bulk-memory"] = true;
+    Features["bulk-memory-opt"] = true;
+    Features["call-indirect-overlong"] = true;
     Features["multivalue"] = true;
     Features["mutable-globals"] = true;
     Features["nontrapping-fptoint"] = true;
@@ -200,6 +206,22 @@ bool WebAssemblyTargetInfo::handleTargetFeatures(
       HasBulkMemory = false;
       continue;
     }
+    if (Feature == "+bulk-memory-opt") {
+      HasBulkMemoryOpt = true;
+      continue;
+    }
+    if (Feature == "-bulk-memory-opt") {
+      HasBulkMemoryOpt = false;
+      continue;
+    }
+    if (Feature == "+call-indirect-overlong") {
+      HasCallIndirectOverlong = true;
+      continue;
+    }
+    if (Feature == "-call-indirect-overlong") {
+      HasCallIndirectOverlong = false;
+      continue;
+    }
     if (Feature == "+exception-handling") {
       HasExceptionHandling = true;
       continue;
@@ -310,6 +332,18 @@ bool WebAssemblyTargetInfo::handleTargetFeatures(
         << Feature << "-target-feature";
     return false;
   }
+
+  // bulk-memory-opt is a subset of bulk-memory.
+  if (HasBulkMemory) {
+    HasBulkMemoryOpt = true;
+  }
+
+  // The reference-types feature included the change to `call_indirect`
+  // encodings to support overlong immediates.
+  if (HasReferenceTypes) {
+    HasCallIndirectOverlong = true;
+  }
+
   return true;
 }