[WebAssembly] v128.const

Summary:
This CL implements v128.const for each vector type. New operand types
are added to ensure the vector contents can be serialized without LEB
encoding. Tests are added for instruction selection, encoding,
assembly and disassembly.

Reviewers: aheejin, dschuff, aardappel

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

Differential Revision: https://reviews.llvm.org/D50873

llvm-svn: 340336

1 files changed, 29 insertions, 4 deletions

diff --git a/llvm/lib/Target/WebAssembly/Disassembler/WebAssemblyDisassembler.cpp b/llvm/lib/Target/WebAssembly/Disassembler/WebAssemblyDisassembler.cpp
index 2f0960271e3..9f6797da3a2 100644
--- a/llvm/lib/Target/WebAssembly/Disassembler/WebAssemblyDisassembler.cpp
+++ b/llvm/lib/Target/WebAssembly/Disassembler/WebAssemblyDisassembler.cpp
@@ -92,14 +92,18 @@ static bool parseLEBImmediate(MCInst &MI, uint64_t &Size,
 }
 
 template <typename T>
-bool parseFPImmediate(MCInst &MI, uint64_t &Size, ArrayRef<uint8_t> Bytes) {
+bool parseImmediate(MCInst &MI, uint64_t &Size, ArrayRef<uint8_t> Bytes) {
   if (Size + sizeof(T) > Bytes.size())
     return false;
   T Val;
   memcpy(&Val, Bytes.data() + Size, sizeof(T));
   support::endian::byte_swap<T, support::endianness::little>(Val);
   Size += sizeof(T);
-  MI.addOperand(MCOperand::createFPImm(static_cast<double>(Val)));
+  if (std::is_floating_point<T>::value) {
+    MI.addOperand(MCOperand::createFPImm(static_cast<double>(Val)));
+  } else {
+    MI.addOperand(MCOperand::createImm(static_cast<int64_t>(Val)));
+  }
   return true;
 }
 
@@ -160,12 +164,33 @@ MCDisassembler::DecodeStatus WebAssemblyDisassembler::getInstruction(
     }
     // FP operands.
     case WebAssembly::OPERAND_F32IMM: {
-      if (!parseFPImmediate<float>(MI, Size, Bytes))
+      if (!parseImmediate<float>(MI, Size, Bytes))
         return MCDisassembler::Fail;
       break;
     }
     case WebAssembly::OPERAND_F64IMM: {
-      if (!parseFPImmediate<double>(MI, Size, Bytes))
+      if (!parseImmediate<double>(MI, Size, Bytes))
+        return MCDisassembler::Fail;
+      break;
+    }
+    // Vector lane operands (not LEB encoded).
+    case WebAssembly::OPERAND_VEC_I8IMM: {
+      if (!parseImmediate<uint8_t>(MI, Size, Bytes))
+        return MCDisassembler::Fail;
+      break;
+    }
+    case WebAssembly::OPERAND_VEC_I16IMM: {
+      if (!parseImmediate<uint16_t>(MI, Size, Bytes))
+        return MCDisassembler::Fail;
+      break;
+    }
+    case WebAssembly::OPERAND_VEC_I32IMM: {
+      if (!parseImmediate<uint32_t>(MI, Size, Bytes))
+        return MCDisassembler::Fail;
+      break;
+    }
+    case WebAssembly::OPERAND_VEC_I64IMM: {
+      if (!parseImmediate<uint64_t>(MI, Size, Bytes))
         return MCDisassembler::Fail;
       break;
     }