[WebAssembly] Add wasm support for llvm-readobj

Create a WasmDumper subclass of ObjDumper to support Webassembly binary
files.

Patch by Sam Clegg

Differential Revision: https://reviews.llvm.org/D27355

llvm-svn: 293569

4 files changed, 99 insertions, 0 deletions

diff --git a/llvm/tools/llvm-readobj/CMakeLists.txt b/llvm/tools/llvm-readobj/CMakeLists.txt
index d4b7125dbbb..5fd45a8cff6 100644
--- a/llvm/tools/llvm-readobj/CMakeLists.txt
+++ b/llvm/tools/llvm-readobj/CMakeLists.txt
@@ -15,5 +15,6 @@ add_llvm_tool(llvm-readobj
   llvm-readobj.cpp
   MachODumper.cpp
   ObjDumper.cpp
+  WasmDumper.cpp
   Win64EHDumper.cpp
   )
diff --git a/llvm/tools/llvm-readobj/ObjDumper.h b/llvm/tools/llvm-readobj/ObjDumper.h
index c91558ecbfa..75090312b21 100644
--- a/llvm/tools/llvm-readobj/ObjDumper.h
+++ b/llvm/tools/llvm-readobj/ObjDumper.h
@@ -96,6 +96,10 @@ std::error_code createMachODumper(const object::ObjectFile *Obj,
                                   ScopedPrinter &Writer,
                                   std::unique_ptr<ObjDumper> &Result);
 
+std::error_code createWasmDumper(const object::ObjectFile *Obj,
+                                 ScopedPrinter &Writer,
+                                 std::unique_ptr<ObjDumper> &Result);
+
 void dumpCOFFImportFile(const object::COFFImportFile *File);
 
 void dumpCodeViewMergedTypes(ScopedPrinter &Writer,
diff --git a/llvm/tools/llvm-readobj/WasmDumper.cpp b/llvm/tools/llvm-readobj/WasmDumper.cpp
new file mode 100644
index 00000000000..8f3ec575e47
--- /dev/null
+++ b/llvm/tools/llvm-readobj/WasmDumper.cpp
@@ -0,0 +1,92 @@
+//===-- WasmDumper.cpp - Wasm-specific object file dumper -----------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the Wasm-specific dumper for llvm-readobj.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Error.h"
+#include "ObjDumper.h"
+#include "llvm/Object/Wasm.h"
+#include "llvm/Support/ScopedPrinter.h"
+
+using namespace llvm;
+using namespace object;
+
+namespace {
+
+const char *wasmSectionTypeToString(uint32_t Type) {
+#define ECase(X)                                                               \
+  case wasm::WASM_SEC_##X:                                                     \
+    return #X;
+  switch (Type) {
+    ECase(CUSTOM);
+    ECase(TYPE);
+    ECase(IMPORT);
+    ECase(FUNCTION);
+    ECase(TABLE);
+    ECase(MEMORY);
+    ECase(GLOBAL);
+    ECase(EXPORT);
+    ECase(START);
+    ECase(ELEM);
+    ECase(CODE);
+    ECase(DATA);
+  }
+#undef ECase
+  return "";
+}
+
+class WasmDumper : public ObjDumper {
+public:
+  WasmDumper(const WasmObjectFile *Obj, ScopedPrinter &Writer)
+      : ObjDumper(Writer), Obj(Obj) {}
+
+  void printFileHeaders() override {
+    W.printHex("Version", Obj->getHeader().Version);
+  }
+
+  void printSections() override {
+    ListScope Group(W, "Sections");
+    for (const SectionRef &Section : Obj->sections()) {
+      const wasm::WasmSection *WasmSec = Obj->getWasmSection(Section);
+      DictScope SectionD(W, "Section");
+      const char *Type = wasmSectionTypeToString(WasmSec->Type);
+      W.printHex("Type", Type, WasmSec->Type);
+      W.printNumber("Size", WasmSec->Content.size());
+      W.printNumber("Offset", WasmSec->Offset);
+      if (WasmSec->Type == wasm::WASM_SEC_CUSTOM) {
+        W.printString("Name", WasmSec->Name);
+      }
+    }
+  }
+  void printRelocations() override { llvm_unreachable("unimplemented"); }
+  void printSymbols() override { llvm_unreachable("unimplemented"); }
+  void printDynamicSymbols() override { llvm_unreachable("unimplemented"); }
+  void printUnwindInfo() override { llvm_unreachable("unimplemented"); }
+  void printStackMap() const override { llvm_unreachable("unimplemented"); }
+
+private:
+  const WasmObjectFile *Obj;
+};
+}
+
+namespace llvm {
+
+std::error_code createWasmDumper(const object::ObjectFile *Obj,
+                                 ScopedPrinter &Writer,
+                                 std::unique_ptr<ObjDumper> &Result) {
+  const WasmObjectFile *WasmObj = dyn_cast<WasmObjectFile>(Obj);
+  assert(WasmObj && "createWasmDumper called with non-wasm object");
+
+  Result.reset(new WasmDumper(WasmObj, Writer));
+  return readobj_error::success;
+}
+
+} // namespace llvm
diff --git a/llvm/tools/llvm-readobj/llvm-readobj.cpp b/llvm/tools/llvm-readobj/llvm-readobj.cpp
index 970e1545de0..fffcd1790e3 100644
--- a/llvm/tools/llvm-readobj/llvm-readobj.cpp
+++ b/llvm/tools/llvm-readobj/llvm-readobj.cpp
@@ -358,6 +358,8 @@ static std::error_code createDumper(const ObjectFile *Obj,
     return createELFDumper(Obj, Writer, Result);
   if (Obj->isMachO())
     return createMachODumper(Obj, Writer, Result);
+  if (Obj->isWasm())
+    return createWasmDumper(Obj, Writer, Result);
 
   return readobj_error::unsupported_obj_file_format;
 }