[WebAssembly] tablegen: distinguish float/int immediate operands.

Summary:
Before, they were one category of operands which could cause
crashes in non-sensical combinations, e.g. "f32.const symbol".
Now these are forced to be an error.

Reviewers: dschuff

Subscribers: sbc100, jgravelle-google, aheejin, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64039

llvm-svn: 365351
diff --git a/llvm/lib/Target/WebAssembly/AsmParser/WebAssemblyAsmParser.cpp b/llvm/lib/Target/WebAssembly/AsmParser/WebAssemblyAsmParser.cpp
index e22ed8e..c7a8890 100644
--- a/llvm/lib/Target/WebAssembly/AsmParser/WebAssemblyAsmParser.cpp
+++ b/llvm/lib/Target/WebAssembly/AsmParser/WebAssemblyAsmParser.cpp
@@ -89,9 +89,8 @@
   }
 
   bool isToken() const override { return Kind == Token; }
-  bool isImm() const override {
-    return Kind == Integer || Kind == Float || Kind == Symbol;
-  }
+  bool isImm() const override { return Kind == Integer || Kind == Symbol; }
+  bool isFPImm() const { return Kind == Float; }
   bool isMem() const override { return false; }
   bool isReg() const override { return false; }
   bool isBrList() const { return Kind == BrList; }
@@ -118,12 +117,18 @@
     assert(N == 1 && "Invalid number of operands!");
     if (Kind == Integer)
       Inst.addOperand(MCOperand::createImm(Int.Val));
-    else if (Kind == Float)
-      Inst.addOperand(MCOperand::createFPImm(Flt.Val));
     else if (Kind == Symbol)
       Inst.addOperand(MCOperand::createExpr(Sym.Exp));
     else
-      llvm_unreachable("Should be immediate or symbol!");
+      llvm_unreachable("Should be integer immediate or symbol!");
+  }
+
+  void addFPImmOperands(MCInst &Inst, unsigned N) const {
+    assert(N == 1 && "Invalid number of operands!");
+    if (Kind == Float)
+      Inst.addOperand(MCOperand::createFPImm(Flt.Val));
+    else
+      llvm_unreachable("Should be float immediate!");
   }
 
   void addBrListOperands(MCInst &Inst, unsigned N) const {