Use ARM/t2PseudoInst class from ARM/Thumb2 special adds/subs patterns.

Clean up the patterns, fix comments, and avoid confusing both tools
and coders. Note that the special adds/subs SelectionDAG nodes no
longer have the dummy cc_out operand.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142397 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 121 insertions, 119 deletions

diff --git a/include/llvm/Target/Target.td b/include/llvm/Target/Target.td
index 6e28f79694..9714172aa4 100644
--- a/include/llvm/Target/Target.td
+++ b/include/llvm/Target/Target.td
@@ -356,6 +356,15 @@ class Instruction {
   // associated with them. Once we've migrated all of them over to true
   // pseudo-instructions that are lowered to real instructions prior to
   // the printer/emitter, we can remove this attribute and just use isPseudo.
+  //
+  // The intended use is:
+  // isPseudo: Does not have encoding information and should be expanded,
+  //   at the latest, during lowering to MCInst.
+  //
+  // isCodeGenOnly: Does have encoding information and can go through to the
+  //   CodeEmitter unchanged, but duplicates a canonical instruction
+  //   definition's encoding and should be ignored when constructing the
+  //   assembler match tables.
   bit isCodeGenOnly = 0;
 
   // Is this instruction a pseudo instruction for use by the assembler parser.
diff --git a/lib/Target/ARM/ARMBaseInstrInfo.cpp b/lib/Target/ARM/ARMBaseInstrInfo.cpp
index 408edfc20d..24cd228279 100644
--- a/lib/Target/ARM/ARMBaseInstrInfo.cpp
+++ b/lib/Target/ARM/ARMBaseInstrInfo.cpp
@@ -1478,7 +1478,6 @@ static AddSubFlagsOpcodePair AddSubFlagsOpcodeMap[] = {
   {ARM::SUBSrsr, ARM::SUBrsr},
 
   {ARM::RSBSri, ARM::RSBri},
-  {ARM::RSBSrr, ARM::RSBrr},
   {ARM::RSBSrsi, ARM::RSBrsi},
   {ARM::RSBSrsr, ARM::RSBrsr},
 
diff --git a/lib/Target/ARM/ARMISelLowering.cpp b/lib/Target/ARM/ARMISelLowering.cpp
index 04b9139815..ac194145e0 100644
--- a/lib/Target/ARM/ARMISelLowering.cpp
+++ b/lib/Target/ARM/ARMISelLowering.cpp
@@ -6319,8 +6319,8 @@ ARMTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
 
 void ARMTargetLowering::AdjustInstrPostInstrSelection(MachineInstr *MI,
                                                       SDNode *Node) const {
-  const MCInstrDesc &MCID = MI->getDesc();
-  if (!MCID.hasPostISelHook()) {
+  const MCInstrDesc *MCID = &MI->getDesc();
+  if (!MCID->hasPostISelHook()) {
     assert(!convertAddSubFlagsOpcode(MI->getOpcode()) &&
            "Pseudo flag-setting opcodes must be marked with 'hasPostISelHook'");
     return;
@@ -6331,20 +6331,28 @@ void ARMTargetLowering::AdjustInstrPostInstrSelection(MachineInstr *MI,
   // operand is still set to noreg. If needed, set the optional operand's
   // register to CPSR, and remove the redundant implicit def.
   //
-  // e.g. ADCS (...opt:%noreg, CPSR<imp-def>) -> ADC (... opt:CPSR<def>).
+  // e.g. ADCS (..., CPSR<imp-def>) -> ADC (... opt:CPSR<def>).
 
   // Rename pseudo opcodes.
   unsigned NewOpc = convertAddSubFlagsOpcode(MI->getOpcode());
   if (NewOpc) {
     const ARMBaseInstrInfo *TII =
       static_cast<const ARMBaseInstrInfo*>(getTargetMachine().getInstrInfo());
-    MI->setDesc(TII->get(NewOpc));
+    MCID = &TII->get(NewOpc);
+
+    assert(MCID->getNumOperands() == MI->getDesc().getNumOperands() + 1 &&
+           "converted opcode should be the same except for cc_out");
+
+    MI->setDesc(*MCID);
+
+    // Add the optional cc_out operand
+    MI->addOperand(MachineOperand::CreateReg(0, /*isDef=*/true));
   }
-  unsigned ccOutIdx = MCID.getNumOperands() - 1;
+  unsigned ccOutIdx = MCID->getNumOperands() - 1;
 
   // Any ARM instruction that sets the 's' bit should specify an optional
   // "cc_out" operand in the last operand position.
-  if (!MCID.hasOptionalDef() || !MCID.OpInfo[ccOutIdx].isOptionalDef()) {
+  if (!MCID->hasOptionalDef() || !MCID->OpInfo[ccOutIdx].isOptionalDef()) {
     assert(!NewOpc && "Optional cc_out operand required");
     return;
   }
@@ -6352,7 +6360,7 @@ void ARMTargetLowering::AdjustInstrPostInstrSelection(MachineInstr *MI,
   // since we already have an optional CPSR def.
   bool definesCPSR = false;
   bool deadCPSR = false;
-  for (unsigned i = MCID.getNumOperands(), e = MI->getNumOperands();
+  for (unsigned i = MCID->getNumOperands(), e = MI->getNumOperands();
        i != e; ++i) {
     const MachineOperand &MO = MI->getOperand(i);
     if (MO.isReg() && MO.isDef() && MO.getReg() == ARM::CPSR) {
diff --git a/lib/Target/ARM/ARMInstrInfo.td b/lib/Target/ARM/ARMInstrInfo.td
index b509110d0b..b9cbc83f21 100644
--- a/lib/Target/ARM/ARMInstrInfo.td
+++ b/lib/Target/ARM/ARMInstrInfo.td
@@ -1040,69 +1040,58 @@ multiclass AsI1_rbin_irs<bits<4> opcod, string opc,
 
 }
 
-/// AsI1_rbin_s_is - Same as AsI1_rbin_s_is except it sets 's' bit by default.
+/// AsI1_bin_s_irs - Same as AsI1_bin_irs except it sets the 's' bit by default.
 ///
 /// These opcodes will be converted to the real non-S opcodes by
-/// AdjustInstrPostInstrSelection after giving then an optional CPSR operand.
-let hasPostISelHook = 1, isCodeGenOnly = 1, isPseudo = 1, Defs = [CPSR] in {
-multiclass AsI1_rbin_s_is<bits<4> opcod, string opc,
-                     InstrItinClass iii, InstrItinClass iir, InstrItinClass iis,
-                        PatFrag opnode, bit Commutable = 0> {
-  def ri : AsI1<opcod, (outs GPR:$Rd), (ins GPR:$Rn, so_imm:$imm), DPFrm,
-               iii, opc, "\t$Rd, $Rn, $imm",
-               [(set GPR:$Rd, CPSR, (opnode so_imm:$imm, GPR:$Rn))]>;
-
-  def rr : AsI1<opcod, (outs GPR:$Rd), (ins GPR:$Rn, GPR:$Rm), DPFrm,
-               iir, opc, "\t$Rd, $Rn, $Rm",
-               [/* pattern left blank */]>;
-
-  def rsi : AsI1<opcod, (outs GPR:$Rd),
-               (ins GPR:$Rn, so_reg_imm:$shift), DPSoRegImmFrm,
-               iis, opc, "\t$Rd, $Rn, $shift",
-               [(set GPR:$Rd, CPSR, (opnode so_reg_imm:$shift, GPR:$Rn))]>;
-
-  def rsr : AsI1<opcod, (outs GPR:$Rd),
-               (ins GPR:$Rn, so_reg_reg:$shift), DPSoRegRegFrm,
-               iis, opc, "\t$Rd, $Rn, $shift",
-               [(set GPR:$Rd, CPSR, (opnode so_reg_reg:$shift, GPR:$Rn))]> {
-    bits<4> Rd;
-    bits<4> Rn;
-    bits<12> shift;
-    let Inst{25} = 0;
-    let Inst{19-16} = Rn;
-    let Inst{15-12} = Rd;
-    let Inst{11-8} = shift{11-8};
-    let Inst{7} = 0;
-    let Inst{6-5} = shift{6-5};
-    let Inst{4} = 1;
-    let Inst{3-0} = shift{3-0};
+/// AdjustInstrPostInstrSelection after giving them an optional CPSR operand.
+let hasPostISelHook = 1, Defs = [CPSR] in {
+multiclass AsI1_bin_s_irs<InstrItinClass iii, InstrItinClass iir,
+                          InstrItinClass iis, PatFrag opnode,
+                          bit Commutable = 0> {
+  def ri : ARMPseudoInst<(outs GPR:$Rd), (ins GPR:$Rn, so_imm:$imm, pred:$p),
+                         4, iii,
+                         [(set GPR:$Rd, CPSR, (opnode GPR:$Rn, so_imm:$imm))]>;
+
+  def rr : ARMPseudoInst<(outs GPR:$Rd), (ins GPR:$Rn, GPR:$Rm, pred:$p),
+                         4, iir,
+                         [(set GPR:$Rd, CPSR, (opnode GPR:$Rn, GPR:$Rm))]> {
+    let isCommutable = Commutable;
   }
+  def rsi : ARMPseudoInst<(outs GPR:$Rd),
+                          (ins GPR:$Rn, so_reg_imm:$shift, pred:$p),
+                          4, iis,
+                          [(set GPR:$Rd, CPSR, (opnode GPR:$Rn,
+                                                so_reg_imm:$shift))]>;
+
+  def rsr : ARMPseudoInst<(outs GPR:$Rd),
+                          (ins GPR:$Rn, so_reg_reg:$shift, pred:$p),
+                          4, iis,
+                          [(set GPR:$Rd, CPSR, (opnode GPR:$Rn,
+                                                so_reg_reg:$shift))]>;
 }
 }
 
-/// AsI1_bin_s_irs - Same as AsI1_bin_irs except it sets the 's' bit by default.
-///
-/// These opcodes will be converted to the real non-S opcodes by
-/// AdjustInstrPostInstrSelection after giving then an optional CPSR operand.
-let hasPostISelHook = 1, isCodeGenOnly = 1, isPseudo = 1, Defs = [CPSR] in {
-multiclass AsI1_bin_s_irs<bits<4> opcod, string opc,
-                     InstrItinClass iii, InstrItinClass iir, InstrItinClass iis,
-                         PatFrag opnode, bit Commutable = 0> {
-  def ri : AsI1<opcod, (outs GPR:$Rd), (ins GPR:$Rn, so_imm:$imm), DPFrm,
-               iii, opc, "\t$Rd, $Rn, $imm",
-               [(set GPR:$Rd, CPSR, (opnode GPR:$Rn, so_imm:$imm))]>;
-  def rr : AsI1<opcod, (outs GPR:$Rd), (ins GPR:$Rn, GPR:$Rm), DPFrm,
-               iir, opc, "\t$Rd, $Rn, $Rm",
-               [(set GPR:$Rd, CPSR, (opnode GPR:$Rn, GPR:$Rm))]>;
-  def rsi : AsI1<opcod, (outs GPR:$Rd),
-               (ins GPR:$Rn, so_reg_imm:$shift), DPSoRegImmFrm,
-               iis, opc, "\t$Rd, $Rn, $shift",
-               [(set GPR:$Rd, CPSR, (opnode GPR:$Rn, so_reg_imm:$shift))]>;
+/// AsI1_rbin_s_is - Same as AsI1_bin_s_irs, except selection DAG
+/// operands are reversed.
+let hasPostISelHook = 1, Defs = [CPSR] in {
+multiclass AsI1_rbin_s_is<InstrItinClass iii, InstrItinClass iir,
+                          InstrItinClass iis, PatFrag opnode,
+                          bit Commutable = 0> {
+  def ri : ARMPseudoInst<(outs GPR:$Rd), (ins GPR:$Rn, so_imm:$imm, pred:$p),
+                         4, iii,
+                         [(set GPR:$Rd, CPSR, (opnode so_imm:$imm, GPR:$Rn))]>;
 
-  def rsr : AsI1<opcod, (outs GPR:$Rd),
-               (ins GPR:$Rn, so_reg_reg:$shift), DPSoRegRegFrm,
-               iis, opc, "\t$Rd, $Rn, $shift",
-               [(set GPR:$Rd, CPSR, (opnode GPR:$Rn, so_reg_reg:$shift))]>;
+  def rsi : ARMPseudoInst<(outs GPR:$Rd),
+                          (ins GPR:$Rn, so_reg_imm:$shift, pred:$p),
+                          4, iis,
+                          [(set GPR:$Rd, CPSR, (opnode so_reg_imm:$shift,
+                                             GPR:$Rn))]>;
+
+  def rsr : ARMPseudoInst<(outs GPR:$Rd),
+                          (ins GPR:$Rn, so_reg_reg:$shift, pred:$p),
+                          4, iis,
+                          [(set GPR:$Rd, CPSR, (opnode so_reg_reg:$shift,
+                                             GPR:$Rn))]>;
 }
 }
 
@@ -2859,7 +2848,7 @@ def MOVr : AsI1<0b1101, (outs GPR:$Rd), (ins GPR:$Rm), DPFrm, IIC_iMOVr,
   let Inst{15-12} = Rd;
 }
 
-def : ARMInstAlias<"movs${p} $Rd, $Rm", 
+def : ARMInstAlias<"movs${p} $Rd, $Rm",
                    (MOVr GPR:$Rd, GPR:$Rm, pred:$p, CPSR)>;
 
 // A version for the smaller set of tail call registers.
@@ -3079,20 +3068,18 @@ defm SUB  : AsI1_bin_irs<0b0010, "sub",
 
 // ADD and SUB with 's' bit set.
 //
-// Currently, t2ADDS/t2SUBS are pseudo opcodes that exist only in the
-// selection DAG. They are "lowered" to real t2ADD/t2SUB opcodes by
+// Currently, ADDS/SUBS are pseudo opcodes that exist only in the
+// selection DAG. They are "lowered" to real ADD/SUB opcodes by
 // AdjustInstrPostInstrSelection where we determine whether or not to
 // set the "s" bit based on CPSR liveness.
 //
-// FIXME: Eliminate t2ADDS/t2SUBS pseudo opcodes after adding tablegen
+// FIXME: Eliminate ADDS/SUBS pseudo opcodes after adding tablegen
 // support for an optional CPSR definition that corresponds to the DAG
 // node's second value. We can then eliminate the implicit def of CPSR.
-defm ADDS : AsI1_bin_s_irs<0b0100, "add",
-                          IIC_iALUi, IIC_iALUr, IIC_iALUsr,
-                          BinOpFrag<(ARMaddc node:$LHS, node:$RHS)>, 1>;
-defm SUBS : AsI1_bin_s_irs<0b0010, "sub",
-                          IIC_iALUi, IIC_iALUr, IIC_iALUsr,
-                          BinOpFrag<(ARMsubc node:$LHS, node:$RHS)>>;
+defm ADDS : AsI1_bin_s_irs<IIC_iALUi, IIC_iALUr, IIC_iALUsr,
+                           BinOpFrag<(ARMaddc node:$LHS, node:$RHS)>, 1>;
+defm SUBS : AsI1_bin_s_irs<IIC_iALUi, IIC_iALUr, IIC_iALUsr,
+                           BinOpFrag<(ARMsubc node:$LHS, node:$RHS)>>;
 
 defm ADC : AI1_adde_sube_irs<0b0101, "adc",
                   BinOpWithFlagFrag<(ARMadde node:$LHS, node:$RHS, node:$FLAG)>,
@@ -3107,9 +3094,8 @@ defm RSB  : AsI1_rbin_irs <0b0011, "rsb",
 
 // FIXME: Eliminate them if we can write def : Pat patterns which defines
 // CPSR and the implicit def of CPSR is not needed.
-defm RSBS : AsI1_rbin_s_is<0b0011, "rsb",
-                         IIC_iALUi, IIC_iALUr, IIC_iALUsr,
-                         BinOpFrag<(ARMsubc node:$LHS, node:$RHS)>>;
+defm RSBS : AsI1_rbin_s_is<IIC_iALUi, IIC_iALUr, IIC_iALUsr,
+                           BinOpFrag<(ARMsubc node:$LHS, node:$RHS)>>;
 
 defm RSC : AI1_rsc_irs<0b0111, "rsc",
                   BinOpWithFlagFrag<(ARMsube node:$LHS, node:$RHS, node:$FLAG)>,
diff --git a/lib/Target/ARM/ARMInstrThumb2.td b/lib/Target/ARM/ARMInstrThumb2.td
index 403d7bc608..9d8505544d 100644
--- a/lib/Target/ARM/ARMInstrThumb2.td
+++ b/lib/Target/ARM/ARMInstrThumb2.td
@@ -608,25 +608,48 @@ multiclass T2I_rbin_irs<bits<4> opcod, string opc, PatFrag opnode> {
 ///
 /// These opcodes will be converted to the real non-S opcodes by
 /// AdjustInstrPostInstrSelection after giving then an optional CPSR operand.
-let hasPostISelHook = 1, isCodeGenOnly = 1, isPseudo = 1, Defs = [CPSR] in {
-multiclass T2I_bin_s_irs<bits<4> opcod, string opc,
-                     InstrItinClass iii, InstrItinClass iir, InstrItinClass iis,
-                         PatFrag opnode, bit Commutable = 0> {
+let hasPostISelHook = 1, Defs = [CPSR] in {
+multiclass T2I_bin_s_irs<InstrItinClass iii, InstrItinClass iir,
+                         InstrItinClass iis, PatFrag opnode,
+                         bit Commutable = 0> {
    // shifted imm
-   def ri : T2sTwoRegImm<
-                (outs rGPR:$Rd), (ins GPRnopc:$Rn, t2_so_imm:$imm), iii,
-                opc, ".w\t$Rd, $Rn, $imm",
-                [(set rGPR:$Rd, CPSR, (opnode GPRnopc:$Rn, t2_so_imm:$imm))]>;
+   def ri : t2PseudoInst<(outs rGPR:$Rd),
+                         (ins GPRnopc:$Rn, t2_so_imm:$imm, pred:$p),
+                         4, iii,
+                         [(set rGPR:$Rd, CPSR, (opnode GPRnopc:$Rn,
+                                                t2_so_imm:$imm))]>;
    // register
-   def rr : T2sThreeReg<
-                (outs rGPR:$Rd), (ins GPRnopc:$Rn, rGPR:$Rm), iir,
-                opc, ".w\t$Rd, $Rn, $Rm",
-                [(set rGPR:$Rd, CPSR, (opnode GPRnopc:$Rn, rGPR:$Rm))]>;
+   def rr : t2PseudoInst<(outs rGPR:$Rd), (ins GPRnopc:$Rn, rGPR:$Rm, pred:$p),
+                         4, iir,
+                         [(set rGPR:$Rd, CPSR, (opnode GPRnopc:$Rn,
+                                                rGPR:$Rm))]> {
+     let isCommutable = Commutable;
+   }
    // shifted register
-   def rs : T2sTwoRegShiftedReg<
-                (outs rGPR:$Rd), (ins GPRnopc:$Rn, t2_so_reg:$ShiftedRm), iis,
-                opc, ".w\t$Rd, $Rn, $ShiftedRm",
-               [(set rGPR:$Rd, CPSR, (opnode GPRnopc:$Rn, t2_so_reg:$ShiftedRm))]>;
+   def rs : t2PseudoInst<(outs rGPR:$Rd),
+                         (ins GPRnopc:$Rn, t2_so_reg:$ShiftedRm, pred:$p),
+                         4, iis,
+                         [(set rGPR:$Rd, CPSR, (opnode GPRnopc:$Rn,
+                                                t2_so_reg:$ShiftedRm))]>;
+}
+}
+
+/// T2I_rbin_s_is -  Same as T2I_bin_s_irs, except selection DAG
+/// operands are reversed.
+let hasPostISelHook = 1, Defs = [CPSR] in {
+multiclass T2I_rbin_s_is<PatFrag opnode> {
+   // shifted imm
+   def ri : t2PseudoInst<(outs rGPR:$Rd),
+                         (ins GPRnopc:$Rn, t2_so_imm:$imm, pred:$p),
+                         4, IIC_iALUi,
+                         [(set rGPR:$Rd, CPSR, (opnode t2_so_imm:$imm,
+                                                GPRnopc:$Rn))]>;
+   // shifted register
+   def rs : t2PseudoInst<(outs rGPR:$Rd),
+                         (ins GPRnopc:$Rn, t2_so_reg:$ShiftedRm, pred:$p),
+                         4, IIC_iALUsi,
+                         [(set rGPR:$Rd, CPSR, (opnode t2_so_reg:$ShiftedRm,
+                                                GPRnopc:$Rn))]>;
 }
 }
 
@@ -735,26 +758,6 @@ multiclass T2I_adde_sube_irs<bits<4> opcod, string opc, PatFrag opnode,
 }
 }
 
-/// T2I_rbin_s_is - Same as T2I_rbin_irs except sets 's' bit and the register
-/// version is not needed since this is only for codegen.
-///
-/// These opcodes will be converted to the real non-S opcodes by
-/// AdjustInstrPostInstrSelection after giving then an optional CPSR operand.
-let hasPostISelHook = 1, isCodeGenOnly = 1, isPseudo = 1, Defs = [CPSR] in {
-multiclass T2I_rbin_s_is<bits<4> opcod, string opc, PatFrag opnode> {
-   // shifted imm
-   def ri : T2sTwoRegImm<
-                (outs rGPR:$Rd), (ins rGPR:$Rn, t2_so_imm:$imm), IIC_iALUi,
-                opc, ".w\t$Rd, $Rn, $imm",
-                [(set rGPR:$Rd, CPSR, (opnode t2_so_imm:$imm, rGPR:$Rn))]>;
-   // shifted register
-   def rs : T2sTwoRegShiftedReg<
-                (outs rGPR:$Rd), (ins rGPR:$Rn, t2_so_reg:$ShiftedRm),
-                IIC_iALUsi, opc, "\t$Rd, $Rn, $ShiftedRm",
-              [(set rGPR:$Rd, CPSR, (opnode t2_so_reg:$ShiftedRm, rGPR:$Rn))]>;
-}
-}
-
 /// T2I_sh_ir - Defines a set of (op reg, {so_imm|r}) patterns for a shift /
 //  rotate operation that produces a value.
 multiclass T2I_sh_ir<bits<2> opcod, string opc, Operand ty, PatFrag opnode,
@@ -1845,11 +1848,9 @@ defm t2SUB  : T2I_bin_ii12rs<0b101, "sub",
 // FIXME: Eliminate t2ADDS/t2SUBS pseudo opcodes after adding tablegen
 // support for an optional CPSR definition that corresponds to the DAG
 // node's second value. We can then eliminate the implicit def of CPSR.
-defm t2ADDS : T2I_bin_s_irs <0b1000, "add",
-                             IIC_iALUi, IIC_iALUr, IIC_iALUsi,
+defm t2ADDS : T2I_bin_s_irs <IIC_iALUi, IIC_iALUr, IIC_iALUsi,
                              BinOpFrag<(ARMaddc node:$LHS, node:$RHS)>, 1>;
-defm t2SUBS : T2I_bin_s_irs <0b1101, "sub",
-                             IIC_iALUi, IIC_iALUr, IIC_iALUsi,
+defm t2SUBS : T2I_bin_s_irs <IIC_iALUi, IIC_iALUr, IIC_iALUsi,
                              BinOpFrag<(ARMsubc node:$LHS, node:$RHS)>>;
 
 let hasPostISelHook = 1 in {
@@ -1865,8 +1866,7 @@ defm t2RSB  : T2I_rbin_irs  <0b1110, "rsb",
 
 // FIXME: Eliminate them if we can write def : Pat patterns which defines
 // CPSR and the implicit def of CPSR is not needed.
-defm t2RSBS : T2I_rbin_s_is <0b1110, "rsb",
-                             BinOpFrag<(ARMsubc node:$LHS, node:$RHS)>>;
+defm t2RSBS : T2I_rbin_s_is <BinOpFrag<(ARMsubc node:$LHS, node:$RHS)>>;
 
 // (sub X, imm) gets canonicalized to (add X, -imm).  Match this form.
 // The assume-no-carry-in form uses the negation of the input since add/sub