[WebAssembly] Refactor WasmSignature and use it for MCSymbolWasm

MCContext does not destroy MCSymbols on shutdown. So, rather than putting
SmallVectors (which may heap-allocate) inside MCSymbolWasm, use unowned pointer
to a WasmSignature instead. The signatures are now owned by the AsmPrinter.
Also uses WasmSignature instead of param and result vectors in TargetStreamer,
and leaves some TODOs for further simplification.

 Differential Revision: https://reviews.llvm.org/D52580

llvm-svn: 343733

1 files changed, 10 insertions, 2 deletions

diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyMachineFunctionInfo.h b/llvm/lib/Target/WebAssembly/WebAssemblyMachineFunctionInfo.h
index 5a2602f..cde44d2 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyMachineFunctionInfo.h
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyMachineFunctionInfo.h
@@ -17,7 +17,9 @@
 #define LLVM_LIB_TARGET_WEBASSEMBLY_WEBASSEMBLYMACHINEFUNCTIONINFO_H
 
 #include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
+#include "llvm/BinaryFormat/Wasm.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/MC/MCSymbolWasm.h"
 
 namespace llvm {
 
@@ -121,10 +123,16 @@ public:
 void ComputeLegalValueVTs(const Function &F, const TargetMachine &TM, Type *Ty,
                           SmallVectorImpl<MVT> &ValueVTs);
 
-void ComputeSignatureVTs(const Function &F, const TargetMachine &TM,
-                         SmallVectorImpl<MVT> &Params,
+// Compute the signature for a given FunctionType (Ty). Note that it's not the
+// signature for F (F is just used to get varous context)
+void ComputeSignatureVTs(const FunctionType *Ty, const Function &F,
+                         const TargetMachine &TM, SmallVectorImpl<MVT> &Params,
                          SmallVectorImpl<MVT> &Results);
 
+std::unique_ptr<wasm::WasmSignature>
+SignatureFromMVTs(const SmallVectorImpl<MVT> &Results,
+                  const SmallVectorImpl<MVT> &Params);
+
 } // end namespace llvm
 
 #endif