Fix the bahavior of the disassembler when decoding unpredictable mrs instructions...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155002 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/ARM/ARMInstrInfo.td b/lib/Target/ARM/ARMInstrInfo.td
index 7b0a3ac42ab87fd3664929963833fa837e1644e0..807577e7696fe9ad42e90bb00388a5567193ba54 100644 (file)
--- a/lib/Target/ARM/ARMInstrInfo.td
+++ b/lib/Target/ARM/ARMInstrInfo.td
@@ -4646,22 +4646,32 @@ def MRRC2 : MovRRCopro2<"mrrc2", 1 /* from coprocessor to ARM core register */>;
 //
 
 // Move to ARM core register from Special Register
-def MRS : ABI<0b0001, (outs GPR:$Rd), (ins), NoItinerary,
+def MRS : ABI<0b0001, (outs GPRnopc:$Rd), (ins), NoItinerary,
               "mrs", "\t$Rd, apsr", []> {
   bits<4> Rd;
   let Inst{23-16} = 0b00001111;
+  let Unpredictable{19-17} = 0b111;
+
   let Inst{15-12} = Rd;
-  let Inst{7-4} = 0b0000;
+
+  let Inst{11-0} = 0b000000000000;
+  let Unpredictable{11-0} = 0b110100001111;
 }
 
-def : InstAlias<"mrs${p} $Rd, cpsr", (MRS GPR:$Rd, pred:$p)>, Requires<[IsARM]>;
+def : InstAlias<"mrs${p} $Rd, cpsr", (MRS GPRnopc:$Rd, pred:$p)>, Requires<[IsARM]>;
 
-def MRSsys : ABI<0b0001, (outs GPR:$Rd), (ins), NoItinerary,
+// The MRSsys instruction is the MRS instruction from the ARM ARM,
+// section B9.3.9, with the R bit set to 1.
+def MRSsys : ABI<0b0001, (outs GPRnopc:$Rd), (ins), NoItinerary,
                  "mrs", "\t$Rd, spsr", []> {
   bits<4> Rd;
   let Inst{23-16} = 0b01001111;
+  let Unpredictable{19-16} = 0b1111;
+
   let Inst{15-12} = Rd;
-  let Inst{7-4} = 0b0000;
+
+  let Inst{11-0} = 0b000000000000;
+  let Unpredictable{11-0} = 0b110100001111;
 }
 
 // Move from ARM core register to Special Register

diff --git a/test/MC/Disassembler/ARM/unpredictable-MRS-arm.txt b/test/MC/Disassembler/ARM/unpredictable-MRS-arm.txt
new file mode 100644 (file)
index 0000000..3e472cd
--- /dev/null
+++ b/test/MC/Disassembler/ARM/unpredictable-MRS-arm.txt
@@ -0,0 +1,18 @@
+# RUN: llvm-mc --disassemble %s -triple=arm-apple-darwin9 |& FileCheck %s
+
+# CHECK: warning: potentially undefined
+# CHECK: 0x00 0xf0 0x0f 0x01
+0x00 0xf0 0x0f 0x01
+
+# CHECK: warning: potentially undefined
+# CHECK: 0x00 0xf0 0x4f 0x01
+0x00 0xf0 0x4f 0x01
+
+# CHECK: warning: potentially undefined
+# CHECK: 0x0f 0x0d 0x01 0x01
+0x0f 0x0d 0x01 0x01
+
+# CHECK: warning: potentially undefined
+# CHECK: 0x0f 0x0d 0x40 0x01
+0x0f 0x0d 0x40 0x01
+