[arm64] Use exclusive instructions in exchange

src/arm64/disasm-arm64.cc

Index: src/arm64/disasm-arm64.cc
diff --git a/src/arm64/disasm-arm64.cc b/src/arm64/disasm-arm64.cc
index 8e022b1690f6e1efe86b344ee4e654e37aeeea8e..ee0132cdc9a4214638783164d8e456ec30eb50fb 100644
--- a/src/arm64/disasm-arm64.cc
+++ b/src/arm64/disasm-arm64.cc
@@ -914,12 +914,55 @@ void DisassemblingDecoder::VisitLoadStorePairOffset(Instruction* instr) {
   Format(instr, mnemonic, form);
 }
 
+void DisassemblingDecoder::VisitLoadStoreExclusive(Instruction* instr) {
+  const char* mnemonic = "unimplemented";
+  const char* form = "'Wt, ['Xns]";
+  const char* form_x = "'Xt, ['Xns]";
+  const char* form_stx = "'Ws, 'Wt, ['Xns]";
+  const char* form_stx_x = "'Ws, 'Xt, ['Xns]";
+
+  switch (instr->Mask(LoadStoreExclusiveMask)) {
+    case STXRB:
+      mnemonic = "stxrb";
+      form = form_stx;
+      break;
+    case LDXRB:
+      mnemonic = "ldxrb";
+      break;
+    case STXRH:
+      mnemonic = "stxrh";
+      form = form_stx;
+      break;
+    case LDXRH:
+      mnemonic = "ldxrh";
+      break;
+    case STXR_w:
+      mnemonic = "stxr";
+      form = form_stx;
+      break;
+    case LDXR_w:
+      mnemonic = "ldxr";
+      break;
+    case STXR_x:
+      mnemonic = "stxr";
+      form = form_stx_x;
+      break;
+    case LDXR_x:
+      mnemonic = "ldxr";
+      form = form_x;
+      break;
+    default:
+      form = "(LoadStoreExclusive)";
+  }
+  Format(instr, mnemonic, form);
+}
+
 void DisassemblingDecoder::VisitLoadStoreAcquireRelease(Instruction *instr) {
   const char *mnemonic = "unimplemented";
-  const char *form = "'Wt, ['Xn]";
-  const char *form_x = "'Xt, ['Xn]";
-  const char *form_stlx = "'Ws, 'Wt, ['Xn]";
-  const char *form_stlx_x = "'Ws, 'Xt, ['Xn]";
+  const char* form = "'Wt, ['Xns]";
+  const char* form_x = "'Xt, ['Xns]";
+  const char* form_stlx = "'Ws, 'Wt, ['Xns]";
+  const char* form_stlx_x = "'Ws, 'Xt, ['Xns]";
 
   switch (instr->Mask(LoadStoreAcquireReleaseMask)) {
     case LDAXR_b: mnemonic = "ldaxrb"; break;
@@ -938,7 +981,8 @@ void DisassemblingDecoder::VisitLoadStoreAcquireRelease(Instruction *instr) {
     case STLXR_b: mnemonic = "stlxrb"; form = form_stlx; break;
     case STLXR_w: mnemonic = "stlxr"; form = form_stlx; break;
     case STLXR_x: mnemonic = "stlxr"; form = form_stlx_x; break;
-    default: form = "(LoadStoreAcquireReleaseMask)";
+    default:
+      form = "(LoadStoreAcquireRelease)";
   }
   Format(instr, mnemonic, form);
 }