MOVs should have Inst{19-16} as 0b0000, otherwise, the instruction is UNPREDICTABLE.

rdar://problem/9224120

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128748 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/ARM/ARMInstrInfo.td b/lib/Target/ARM/ARMInstrInfo.td
index 2f9da43a5b4b829877a5d154b26c48210a372575..28b53ca67cbce646ff72f904b399ee923d0d69e8 100644 (file)
--- a/lib/Target/ARM/ARMInstrInfo.td
+++ b/lib/Target/ARM/ARMInstrInfo.td
@@ -2009,6 +2009,7 @@ def MOVs : AsI1<0b1101, (outs GPR:$Rd), (ins shift_so_reg:$src),
   bits<4> Rd;
   bits<12> src;
   let Inst{15-12} = Rd;
+  let Inst{19-16} = 0b0000;
   let Inst{11-0} = src;
   let Inst{25} = 0;
 }

diff --git a/test/MC/Disassembler/ARM/invalid-MOVs-arm.txt b/test/MC/Disassembler/ARM/invalid-MOVs-arm.txt
new file mode 100644 (file)
index 0000000..cfbba43
--- /dev/null
+++ b/test/MC/Disassembler/ARM/invalid-MOVs-arm.txt
@@ -0,0 +1,17 @@
+# RUN: llvm-mc --disassemble %s -triple=arm-apple-darwin9 |& grep {invalid instruction encoding}
+
+# Opcode=0 Name=PHI Format=(42)
+#  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 
+# -------------------------------------------------------------------------------------------------
+# | 1: 1: 1: 1| 0: 0: 0: 1| 1: 0: 1: 1| 1: 1: 0: 0| 1: 1: 0: 1| 0: 0: 0: 1| 0: 0: 0: 0| 0: 0: 1: 0|
+# -------------------------------------------------------------------------------------------------
+# To qualify as an LSL (immediate) instruction, Inst{19-16} "should" be 0b0000, instead it is = 0b1100.
+# The instruction is UNPREDICTABLE, and is not a valid intruction.
+#
+# See also
+# A8.6.88 LSL (immediate)
+# A8.6.98 MOV (shifted register), and
+# I.1 Instruction encoding diagrams and pseudocode
+0x2 0xd1 0xbc 0xf1
+
+