[llvm-commits] [llvm] r138143 - in /llvm/trunk: lib/Target/ARM/ARMInstrThumb.td lib/Target/ARM/AsmParser/ARMAsmParser.cpp lib/Target/ARM/InstPrinter/ARMInstPrinter.cpp test/MC/ARM/basic-thumb-instructions.s test/MC/ARM/thumb.s

[Jim Grosbach]

Author: grosbach
Date: Fri Aug 19 18:24:36 2011
New Revision: 138143

URL: http://llvm.org/viewvc/llvm-project?rev=138143&view=rev
Log:
Thumb parsing and encoding support for NOP.

The irony is not lost that this is not a completely trivial patchset.

Modified:
    llvm/trunk/lib/Target/ARM/ARMInstrThumb.td
    llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
    llvm/trunk/lib/Target/ARM/InstPrinter/ARMInstPrinter.cpp
    llvm/trunk/test/MC/ARM/basic-thumb-instructions.s
    llvm/trunk/test/MC/ARM/thumb.s

Modified: llvm/trunk/lib/Target/ARM/ARMInstrThumb.td
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMInstrThumb.td?rev=138143&r1=138142&r2=138143&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMInstrThumb.td (original)
+++ llvm/trunk/lib/Target/ARM/ARMInstrThumb.td Fri Aug 19 18:24:36 2011
@@ -237,7 +237,8 @@
 }
 
 def tNOP : T1pI<(outs), (ins), NoItinerary, "nop", "", []>,
-           T1SystemEncoding<0x00>; // A8.6.110
+           T1SystemEncoding<0x00>, // A8.6.110
+        Requires<[IsThumb2]>;
 
 def tYIELD : T1pI<(outs), (ins), NoItinerary, "yield", "", []>,
            T1SystemEncoding<0x10>; // A8.6.410
@@ -1382,3 +1383,8 @@
                   2, IIC_Br, [(brind GPR:$Rm)],
                   (tMOVr PC, GPR:$Rm, pred:$p)>;
 }
+
+
+// In Thumb1, "nop" is encoded as a "mov r8, r8". Technically, the bf00
+// encoding is available on ARMv6K, but we don't differentiate that finely.
+def : InstAlias<"nop", (tMOVr R8, R8, 14, 0)>,Requires<[IsThumb, IsThumb1Only]>;

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=138143&r1=138142&r2=138143&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp (original)
+++ llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp Fri Aug 19 18:24:36 2011
@@ -2846,6 +2846,7 @@
       Mnemonic == "trap" || Mnemonic == "mrc2" || Mnemonic == "mrrc2" ||
       Mnemonic == "dsb" || Mnemonic == "isb" || Mnemonic == "clrex" ||
       Mnemonic == "setend" ||
+      (Mnemonic == "nop" && isThumbOne()) ||
       ((Mnemonic == "pld" || Mnemonic == "pli") && !isThumb()) ||
       ((Mnemonic.startswith("rfe") || Mnemonic.startswith("srs"))
         && !isThumb()) ||

Modified: llvm/trunk/lib/Target/ARM/InstPrinter/ARMInstPrinter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/InstPrinter/ARMInstPrinter.cpp?rev=138143&r1=138142&r2=138143&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/InstPrinter/ARMInstPrinter.cpp (original)
+++ llvm/trunk/lib/Target/ARM/InstPrinter/ARMInstPrinter.cpp Fri Aug 19 18:24:36 2011
@@ -169,6 +169,13 @@
     return;
   }
 
+  // Thumb1 NOP
+  if (Opcode == ARM::tMOVr && MI->getOperand(0).getReg() == ARM::R8 &&
+      MI->getOperand(1).getReg() == ARM::R8) {
+    O << "\tnop";
+    return;
+  }
+
   printInstruction(MI, O);
 }
 

Modified: llvm/trunk/test/MC/ARM/basic-thumb-instructions.s
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/MC/ARM/basic-thumb-instructions.s?rev=138143&r1=138142&r2=138143&view=diff
==============================================================================
--- llvm/trunk/test/MC/ARM/basic-thumb-instructions.s (original)
+++ llvm/trunk/test/MC/ARM/basic-thumb-instructions.s Fri Aug 19 18:24:36 2011
@@ -347,3 +347,11 @@
         negs r3, r4
 
 @ CHECK: rsbs	r3, r4, #0              @ encoding: [0x63,0x42]
+
+
+ at ------------------------------------------------------------------------------
+@ NOP
+ at ------------------------------------------------------------------------------
+        nop
+
+@ CHECK: nop                            @ encoding: [0xc0,0x46]

Modified: llvm/trunk/test/MC/ARM/thumb.s
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/MC/ARM/thumb.s?rev=138143&r1=138142&r2=138143&view=diff
==============================================================================
--- llvm/trunk/test/MC/ARM/thumb.s (original)
+++ llvm/trunk/test/MC/ARM/thumb.s Fri Aug 19 18:24:36 2011
@@ -42,7 +42,7 @@
 @ CHECK: bkpt  #2                       @ encoding: [0x02,0xbe]
 
         nop
-@ CHECK: nop @ encoding: [0x00,0xbf]
+@ CHECK: nop @ encoding: [0xc0,0x46]
 
         wfe
         wfi