Implement a few more binary encoding bits. Still very early stage proof-of-

concept level stuff at this point, but it is generally working for those
instructions that know how to map the operands.

This patch fills in the register operands for add/sub/or/etc instructions
and adds the conditional execution predicate encoding.

llvm-svn: 116112

Author: Jim Grosbach

llvm/lib/Target/ARM/ARMInstrInfo.td

@@ -481,9 +481,17 @@ multiclass AsI1_bin_irs<bits<4> opcod, string opc,
   def rr : AsI1<opcod, (outs GPR:$dst), (ins GPR:$a, GPR:$b), DPFrm,
                iir, opc, "\t$dst, $a, $b",
                [(set GPR:$dst, (opnode GPR:$a, GPR:$b))]> {
+    bits<4> Rd;
+    bits<4> Rn;
+    bits<4> Rm;
+    bits<4> Cond;
     let Inst{11-4} = 0b00000000;
     let Inst{25} = 0;
     let isCommutable = Commutable;
+    let Inst{3-0} = Rm;
+    let Inst{15-12} = Rd;
+    let Inst{19-16} = Rn;
+    let Inst{31-28} = Cond;
   }
   def rs : AsI1<opcod, (outs GPR:$dst), (ins GPR:$a, so_reg:$b), DPSoRegFrm,
                iis, opc, "\t$dst, $a, $b",
@@ -907,20 +915,24 @@ let isReturn = 1, isTerminator = 1, isBarrier = 1 in {
   def BX_RET : AI<(outs), (ins), BrMiscFrm, IIC_Br,
                   "bx", "\tlr", [(ARMretflag)]>,
                Requires<[IsARM, HasV4T]> {
+    bits<4> Cond;
     let Inst{3-0}   = 0b1110;
     let Inst{7-4}   = 0b0001;
     let Inst{19-8}  = 0b111111111111;
     let Inst{27-20} = 0b00010010;
+    let Inst{31-28} = Cond;
   }
 
   // ARMV4 only
   def MOVPCLR : AI<(outs), (ins), BrMiscFrm, IIC_Br, 
                   "mov", "\tpc, lr", [(ARMretflag)]>,
                Requires<[IsARM, NoV4T]> {
+    bits<4> Cond;
     let Inst{11-0}  = 0b000000001110;
     let Inst{15-12} = 0b1111;
     let Inst{19-16} = 0b0000;
     let Inst{27-20} = 0b00011010;
+    let Inst{31-28} = Cond;
   }
 }
 
@@ -930,21 +942,27 @@ let isBranch = 1, isTerminator = 1, isBarrier = 1, isIndirectBranch = 1 in {
   def BRIND : AXI<(outs), (ins GPR:$dst), BrMiscFrm, IIC_Br, "bx\t$dst",
                   [(brind GPR:$dst)]>,
               Requires<[IsARM, HasV4T]> {
+    bits<4> Rm;
+
     let Inst{7-4}   = 0b0001;
     let Inst{19-8}  = 0b111111111111;
     let Inst{27-20} = 0b00010010;
     let Inst{31-28} = 0b1110;
+    let Inst{3-0}   = Rm;
   }
 
   // ARMV4 only
   def MOVPCRX : AXI<(outs), (ins GPR:$dst), BrMiscFrm, IIC_Br, "mov\tpc, $dst",
                   [(brind GPR:$dst)]>,
               Requires<[IsARM, NoV4T]> {
+    bits<4> Rm;
+
     let Inst{11-4}  = 0b00000000;
     let Inst{15-12} = 0b1111;
     let Inst{19-16} = 0b0000;
     let Inst{27-20} = 0b00011010;
     let Inst{31-28} = 0b1110;
+    let Inst{3-0}   = Rm;
   }
 }
 
@@ -981,9 +999,11 @@ let isCall = 1,
                 IIC_Br, "blx\t$func",
                 [(ARMcall GPR:$func)]>,
             Requires<[IsARM, HasV5T, IsNotDarwin]> {
+    bits<4> Rm;
     let Inst{7-4}   = 0b0011;
     let Inst{19-8}  = 0b111111111111;
     let Inst{27-20} = 0b00010010;
+    let Inst{3-0}   = Rm;
   }
 
   // ARMv4T
@@ -1493,16 +1513,26 @@ def STM_UPD : AXI4st<(outs GPR:$wb), (ins addrmode4:$addr, pred:$p,
 let neverHasSideEffects = 1 in
 def MOVr : AsI1<0b1101, (outs GPR:$dst), (ins GPR:$src), DPFrm, IIC_iMOVr,
                 "mov", "\t$dst, $src", []>, UnaryDP {
+  bits<4> Rd;
+  bits<4> Rm;
+
   let Inst{11-4} = 0b00000000;
   let Inst{25} = 0;
+  let Inst{3-0} = Rm;
+  let Inst{15-12} = Rd;
 }
 
 // A version for the smaller set of tail call registers.
 let neverHasSideEffects = 1 in
 def MOVr_TC : AsI1<0b1101, (outs tcGPR:$dst), (ins tcGPR:$src), DPFrm, 
                 IIC_iMOVr, "mov", "\t$dst, $src", []>, UnaryDP {
+  bits<4> Rd;
+  bits<4> Rm;
+
   let Inst{11-4} = 0b00000000;
   let Inst{25} = 0;
+  let Inst{3-0} = Rm;
+  let Inst{15-12} = Rd;
 }
 
 def MOVs : AsI1<0b1101, (outs GPR:$dst), (ins so_reg:$src),

llvm/lib/Target/ARM/ARMMCCodeEmitter.cpp

@@ -106,6 +106,25 @@ EmitImmediate(const MCOperand &DispOp, unsigned Size, MCFixupKind FixupKind,
   assert(0 && "ARMMCCodeEmitter::EmitImmediate() not yet implemented.");
 }
 
+/// getMachineOpValue - Return binary encoding of operand. If the machine
+/// operand requires relocation, record the relocation and return zero.
+unsigned ARMMCCodeEmitter::getMachineOpValue(const MCInst &MI,
+                                             const MCOperand &MO) const {
+  if (MO.isReg())
+    // FIXME: Should shifted register stuff be handled as part of this? Maybe.
+    return getARMRegisterNumbering(MO.getReg());
+  else if (MO.isImm())
+    // FIXME: This is insufficient. Shifted immediates and all that... (blech).
+    return static_cast<unsigned>(MO.getImm());
+  else {
+#ifndef NDEBUG
+    errs() << MO;
+#endif
+    llvm_unreachable(0);
+  }
+  return 0;
+}
+
 void ARMMCCodeEmitter::
 EncodeInstruction(const MCInst &MI, raw_ostream &OS,
                   SmallVectorImpl<MCFixup> &Fixups) const {

llvm/test/MC/ARM/simple-encoding.ll

@@ -9,10 +9,18 @@ define i32 @foo(i32 %a, i32 %b) nounwind ssp {
 entry:
 ; CHECK: foo
 ; CHECK: 0xf0,0x00,0xf0,0x07
-; CHECK: 0x1e,0xff,0x2f,0x01
+; CHECK: 0x1e,0xff,0x2f,0xe1
 
   tail call void @llvm.trap()
   ret i32 undef
 }
 
+define i32 @f2(i32 %a, i32 %b) nounwind readnone ssp {
+entry:
+; CHECK: f2
+; CHECK: 0x00,0x00,0x81,0xe0
+; CHECK: 0x1e,0xff,0x2f,0xe1
+  %add = add nsw i32 %b, %a
+  ret i32 %add
+}
 declare void @llvm.trap() nounwind