1 files changed, 41 insertions, 31 deletions

diff --git a/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyMCCodeEmitter.cpp b/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyMCCodeEmitter.cpp
index aaca213c4afe..807fd42b8cf6 100644
--- a/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyMCCodeEmitter.cpp
+++ b/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyMCCodeEmitter.cpp
@@ -13,14 +13,12 @@
 
 #include "MCTargetDesc/WebAssemblyFixupKinds.h"
 #include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
-#include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/MC/MCCodeEmitter.h"
 #include "llvm/MC/MCContext.h"
 #include "llvm/MC/MCFixup.h"
 #include "llvm/MC/MCInst.h"
 #include "llvm/MC/MCInstrInfo.h"
-#include "llvm/MC/MCRegisterInfo.h"
 #include "llvm/MC/MCSubtargetInfo.h"
 #include "llvm/MC/MCSymbol.h"
 #include "llvm/Support/Debug.h"
@@ -82,14 +80,15 @@ void WebAssemblyMCCodeEmitter::encodeInstruction(
   // For br_table instructions, encode the size of the table. In the MCInst,
   // there's an index operand (if not a stack instruction), one operand for
   // each table entry, and the default operand.
-  if (MI.getOpcode() == WebAssembly::BR_TABLE_I32_S ||
-      MI.getOpcode() == WebAssembly::BR_TABLE_I64_S)
+  unsigned Opcode = MI.getOpcode();
+  if (Opcode == WebAssembly::BR_TABLE_I32_S ||
+      Opcode == WebAssembly::BR_TABLE_I64_S)
     encodeULEB128(MI.getNumOperands() - 1, OS);
-  if (MI.getOpcode() == WebAssembly::BR_TABLE_I32 ||
-      MI.getOpcode() == WebAssembly::BR_TABLE_I64)
+  if (Opcode == WebAssembly::BR_TABLE_I32 ||
+      Opcode == WebAssembly::BR_TABLE_I64)
     encodeULEB128(MI.getNumOperands() - 2, OS);
 
-  const MCInstrDesc &Desc = MCII.get(MI.getOpcode());
+  const MCInstrDesc &Desc = MCII.get(Opcode);
   for (unsigned I = 0, E = MI.getNumOperands(); I < E; ++I) {
     const MCOperand &MO = MI.getOperand(I);
     if (MO.isReg()) {
@@ -136,7 +135,12 @@ void WebAssemblyMCCodeEmitter::encodeInstruction(
           encodeULEB128(uint64_t(MO.getImm()), OS);
         }
       } else {
-        encodeULEB128(uint64_t(MO.getImm()), OS);
+        // Variadic immediate operands are br_table's destination operands or
+        // try_table's operands (# of catch clauses, catch sub-opcodes, or catch
+        // clause destinations)
+        assert(WebAssembly::isBrTable(Opcode) ||
+               Opcode == WebAssembly::TRY_TABLE_S);
+        encodeULEB128(uint32_t(MO.getImm()), OS);
       }
 
     } else if (MO.isSFPImm()) {
@@ -146,32 +150,38 @@ void WebAssemblyMCCodeEmitter::encodeInstruction(
       uint64_t D = MO.getDFPImm();
       support::endian::write<uint64_t>(OS, D, llvm::endianness::little);
     } else if (MO.isExpr()) {
-      const MCOperandInfo &Info = Desc.operands()[I];
       llvm::MCFixupKind FixupKind;
       size_t PaddedSize = 5;
-      switch (Info.OperandType) {
-      case WebAssembly::OPERAND_I32IMM:
-        FixupKind = MCFixupKind(WebAssembly::fixup_sleb128_i32);
-        break;
-      case WebAssembly::OPERAND_I64IMM:
-        FixupKind = MCFixupKind(WebAssembly::fixup_sleb128_i64);
-        PaddedSize = 10;
-        break;
-      case WebAssembly::OPERAND_FUNCTION32:
-      case WebAssembly::OPERAND_TABLE:
-      case WebAssembly::OPERAND_OFFSET32:
-      case WebAssembly::OPERAND_SIGNATURE:
-      case WebAssembly::OPERAND_TYPEINDEX:
-      case WebAssembly::OPERAND_GLOBAL:
-      case WebAssembly::OPERAND_TAG:
+      if (I < Desc.getNumOperands()) {
+        const MCOperandInfo &Info = Desc.operands()[I];
+        switch (Info.OperandType) {
+        case WebAssembly::OPERAND_I32IMM:
+          FixupKind = MCFixupKind(WebAssembly::fixup_sleb128_i32);
+          break;
+        case WebAssembly::OPERAND_I64IMM:
+          FixupKind = MCFixupKind(WebAssembly::fixup_sleb128_i64);
+          PaddedSize = 10;
+          break;
+        case WebAssembly::OPERAND_FUNCTION32:
+        case WebAssembly::OPERAND_TABLE:
+        case WebAssembly::OPERAND_OFFSET32:
+        case WebAssembly::OPERAND_SIGNATURE:
+        case WebAssembly::OPERAND_TYPEINDEX:
+        case WebAssembly::OPERAND_GLOBAL:
+        case WebAssembly::OPERAND_TAG:
+          FixupKind = MCFixupKind(WebAssembly::fixup_uleb128_i32);
+          break;
+        case WebAssembly::OPERAND_OFFSET64:
+          FixupKind = MCFixupKind(WebAssembly::fixup_uleb128_i64);
+          PaddedSize = 10;
+          break;
+        default:
+          llvm_unreachable("unexpected symbolic operand kind");
+        }
+      } else {
+        // Variadic expr operands are try_table's catch/catch_ref clauses' tags.
+        assert(Opcode == WebAssembly::TRY_TABLE_S);
         FixupKind = MCFixupKind(WebAssembly::fixup_uleb128_i32);
-        break;
-      case WebAssembly::OPERAND_OFFSET64:
-        FixupKind = MCFixupKind(WebAssembly::fixup_uleb128_i64);
-        PaddedSize = 10;
-        break;
-      default:
-        llvm_unreachable("unexpected symbolic operand kind");
       }
       Fixups.push_back(MCFixup::create(OS.tell() - Start, MO.getExpr(),
                                        FixupKind, MI.getLoc()));