[llvm] r177463 - Fix pr13145 - Naming a function like a register name confuses the asm parser.

[Chad Rosier]

Author: mcrosier
Date: Tue Mar 19 18:44:03 2013
New Revision: 177463

URL: http://llvm.org/viewvc/llvm-project?rev=177463&view=rev
Log:
Fix pr13145 - Naming a function like a register name confuses the asm parser.
Patch by Stepan Dyatkovskiy <stpworld at narod.ru>
rdar://13457826

Added:
    llvm/trunk/test/MC/ARM/2013-03-18-Br-to-label-named-like-reg.s
Modified:
    llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp

Modified: llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp?rev=177463&r1=177462&r2=177463&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp (original)
+++ llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp Tue Mar 19 18:44:03 2013
@@ -4593,20 +4593,26 @@ bool ARMAsmParser::parseOperand(SmallVec
     Error(Parser.getTok().getLoc(), "unexpected token in operand");
     return true;
   case AsmToken::Identifier: {
-    if (!tryParseRegisterWithWriteBack(Operands))
-      return false;
-    int Res = tryParseShiftRegister(Operands);
-    if (Res == 0) // success
-      return false;
-    else if (Res == -1) // irrecoverable error
-      return true;
-    // If this is VMRS, check for the apsr_nzcv operand.
-    if (Mnemonic == "vmrs" &&
-        Parser.getTok().getString().equals_lower("apsr_nzcv")) {
-      S = Parser.getTok().getLoc();
-      Parser.Lex();
-      Operands.push_back(ARMOperand::CreateToken("APSR_nzcv", S));
-      return false;
+    // If we've seen a branch mnemonic, the next operand must be a label.  This
+    // is true even if the label is a register name.  So "br r1" means branch to
+    // label "r1".
+    bool ExpectLabel = Mnemonic == "b" || Mnemonic == "bl";
+    if (!ExpectLabel) {
+      if (!tryParseRegisterWithWriteBack(Operands))
+        return false;
+      int Res = tryParseShiftRegister(Operands);
+      if (Res == 0) // success
+        return false;
+      else if (Res == -1) // irrecoverable error
+        return true;
+      // If this is VMRS, check for the apsr_nzcv operand.
+      if (Mnemonic == "vmrs" &&
+          Parser.getTok().getString().equals_lower("apsr_nzcv")) {
+        S = Parser.getTok().getLoc();
+        Parser.Lex();
+        Operands.push_back(ARMOperand::CreateToken("APSR_nzcv", S));
+        return false;
+      }
     }
 
     // Fall though for the Identifier case that is not a register or a

Added: llvm/trunk/test/MC/ARM/2013-03-18-Br-to-label-named-like-reg.s
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/MC/ARM/2013-03-18-Br-to-label-named-like-reg.s?rev=177463&view=auto
==============================================================================
--- llvm/trunk/test/MC/ARM/2013-03-18-Br-to-label-named-like-reg.s (added)
+++ llvm/trunk/test/MC/ARM/2013-03-18-Br-to-label-named-like-reg.s Tue Mar 19 18:44:03 2013
@@ -0,0 +1,5 @@
+@ RUN: llvm-mc -arch arm %s
+@ CHECK: test:
+@ CHECK: br r1
+test:
+  bl r1