A8.6.16 B

Encoding T1 (tBcc)
if cond == '1110' then UNDEFINED;

rdar://problem/9268681

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129325 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/ARM/Disassembler/ThumbDisassemblerCore.h b/lib/Target/ARM/Disassembler/ThumbDisassemblerCore.h
index 85816e02fef4789ef25a902799ad1ae0a04f10b7..480f8bb2bd746b36b27dc7163bd87e56d0f22299 100644 (file)
--- a/lib/Target/ARM/Disassembler/ThumbDisassemblerCore.h
+++ b/lib/Target/ARM/Disassembler/ThumbDisassemblerCore.h
@@ -951,6 +951,11 @@ static bool DisassembleThumb1CondBr(MCInst &MI, unsigned Opcode, uint32_t insn,
                                       : (int)Imm8));
 
   // Predicate operands by ARMBasicMCBuilder::TryPredicateAndSBitModifier().
+  // But note that for tBcc, if cond = '1110' then UNDEFINED.
+  if (Opcode == ARM::tBcc && slice(insn, 11, 8) == 14) {
+    DEBUG(errs() << "if cond = '1110' then UNDEFINED\n");
+    return false;
+  }
   NumOpsAdded = 1;
 
   return true;

diff --git a/test/MC/Disassembler/ARM/invalid-Bcc-thumb.txt b/test/MC/Disassembler/ARM/invalid-Bcc-thumb.txt
new file mode 100644 (file)
index 0000000..66c43c2
--- /dev/null
+++ b/test/MC/Disassembler/ARM/invalid-Bcc-thumb.txt
@@ -0,0 +1,10 @@
+# RUN: llvm-mc --disassemble %s -triple=thumb-apple-darwin9 |& grep {invalid instruction encoding}
+
+# Opcode=2249 Name=tBcc Format=ARM_FORMAT_THUMBFRM(25)
+#  31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10  9  8  7  6  5  4  3  2  1  0 
+# -------------------------------------------------------------------------------------------------
+# | 0: 0: 0: 0| 0: 0: 0: 0| 0: 0: 0: 0| 0: 0: 0: 0| 1: 1: 0: 1| 1: 1: 1: 0| 0: 1: 1: 0| 1: 1: 1: 1|
+# -------------------------------------------------------------------------------------------------
+# 
+# if cond = '1110' then UNDEFINED
+0x6f 0xde