commit 8b22778431cdeb112366ed5dc6283b3a7af19018
author Owen Anderson <resistor@mac.com> Fri Sep 16 23:04:48 2011 +0000
committer Owen Anderson <resistor@mac.com> Fri Sep 16 23:04:48 2011 +0000
tree ed3c0bb4278d9c055d3c9e41fa43f7b677cc1d9b
parent 166e0539c987a5bea2432354b2437eba29bb1ce0

Fix bitfield decoding based on Eli's feedback.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139969 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/ARM/Disassembler/ARMDisassembler.cpp

diff --git a/lib/Target/ARM/Disassembler/ARMDisassembler.cpp b/lib/Target/ARM/Disassembler/ARMDisassembler.cpp
index d1eb5b3..4e9c3e5 100644
--- a/lib/Target/ARM/Disassembler/ARMDisassembler.cpp
+++ b/lib/Target/ARM/Disassembler/ARMDisassembler.cpp
@@ -1004,10 +1004,9 @@
   unsigned msb = fieldFromInstruction32(Val, 5, 5);
   unsigned lsb = fieldFromInstruction32(Val, 0, 5);
 
-  uint32_t msb_mask = (1 << (msb+1)) - 1;
-  if (msb == 31) msb_mask = 0xFFFFFFFF;
-  uint32_t lsb_mask = (1 << lsb) - 1;
-  if (lsb == 31) lsb_mask = 0xFFFFFFFF;
+  uint32_t msb_mask = 0xFFFFFFFF;
+  if (msb != 31) msb_mask = (1U << (msb+1)) - 1;
+  uint32_t lsb_mask = (1U << lsb) - 1;
 
   Inst.addOperand(MCOperand::CreateImm(~(msb_mask ^ lsb_mask)));
   return MCDisassembler::Success;