This adds a new field isAdd to MCInstrDesc. The ARM and Hexagon instruction

descriptions now tag add instructions, and the Hexagon backend is using this to
identify loop induction statements.

Patch by Sam Parker and Sjoerd Meijer.

Differential Revision: https://reviews.llvm.org/D23601

llvm-svn: 281304

5 files changed, 52 insertions, 49 deletions

diff --git a/llvm/lib/Target/ARM/ARMInstrInfo.td b/llvm/lib/Target/ARM/ARMInstrInfo.td
index cda8bb70f1c..2f1b12d7293 100644
--- a/llvm/lib/Target/ARM/ARMInstrInfo.td
+++ b/llvm/lib/Target/ARM/ARMInstrInfo.td
@@ -3498,6 +3498,7 @@ def UBFX  : I<(outs GPRnopc:$Rd),
 //  Arithmetic Instructions.
 //
 
+let isAdd = 1 in
 defm ADD  : AsI1_bin_irs<0b0100, "add",
                          IIC_iALUi, IIC_iALUr, IIC_iALUsr, add, 1>;
 defm SUB  : AsI1_bin_irs<0b0010, "sub",
@@ -3513,9 +3514,11 @@ defm SUB  : AsI1_bin_irs<0b0010, "sub",
 // 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.
+let isAdd = 1 in
 defm ADDS : AsI1_bin_s_irs<IIC_iALUi, IIC_iALUr, IIC_iALUsr, ARMaddc, 1>;
 defm SUBS : AsI1_bin_s_irs<IIC_iALUi, IIC_iALUr, IIC_iALUsr, ARMsubc>;
 
+let isAdd = 1 in
 defm ADC : AI1_adde_sube_irs<0b0101, "adc", ARMadde, 1>;
 defm SBC : AI1_adde_sube_irs<0b0110, "sbc", ARMsube>;
 
diff --git a/llvm/lib/Target/ARM/ARMInstrThumb.td b/llvm/lib/Target/ARM/ARMInstrThumb.td
index 93a174f3678..72623a45034 100644
--- a/llvm/lib/Target/ARM/ARMInstrThumb.td
+++ b/llvm/lib/Target/ARM/ARMInstrThumb.td
@@ -904,49 +904,51 @@ class T1sItGenEncodeImm<bits<5> opA, dag oops, dag iops, InstrItinClass itin,
   let Inst{7-0}  = imm8;
 }
 
-// Add with carry register
-let isCommutable = 1, Uses = [CPSR] in
-def tADC :                      // A8.6.2
-  T1sItDPEncode<0b0101, (outs tGPR:$Rdn), (ins tGPR:$Rn, tGPR:$Rm), IIC_iALUr,
-                "adc", "\t$Rdn, $Rm",
-                [(set tGPR:$Rdn, (adde tGPR:$Rn, tGPR:$Rm))]>, Sched<[WriteALU]>;
-
-// Add immediate
-def tADDi3 :                    // A8.6.4 T1
-  T1sIGenEncodeImm<0b01110, (outs tGPR:$Rd), (ins tGPR:$Rm, imm0_7:$imm3),
-                   IIC_iALUi,
-                   "add", "\t$Rd, $Rm, $imm3",
-                   [(set tGPR:$Rd, (add tGPR:$Rm, imm0_7:$imm3))]>,
-                   Sched<[WriteALU]> {
-  bits<3> imm3;
-  let Inst{8-6} = imm3;
-}
-
-def tADDi8 :                    // A8.6.4 T2
-  T1sItGenEncodeImm<{1,1,0,?,?}, (outs tGPR:$Rdn),
-                    (ins tGPR:$Rn, imm0_255:$imm8), IIC_iALUi,
-                    "add", "\t$Rdn, $imm8",
-                    [(set tGPR:$Rdn, (add tGPR:$Rn, imm8_255:$imm8))]>,
-                    Sched<[WriteALU]>;
+let isAdd = 1 in {
+  // Add with carry register
+  let isCommutable = 1, Uses = [CPSR] in
+  def tADC :                      // A8.6.2
+    T1sItDPEncode<0b0101, (outs tGPR:$Rdn), (ins tGPR:$Rn, tGPR:$Rm), IIC_iALUr,
+                  "adc", "\t$Rdn, $Rm",
+                  [(set tGPR:$Rdn, (adde tGPR:$Rn, tGPR:$Rm))]>, Sched<[WriteALU]>;
+
+  // Add immediate
+  def tADDi3 :                    // A8.6.4 T1
+    T1sIGenEncodeImm<0b01110, (outs tGPR:$Rd), (ins tGPR:$Rm, imm0_7:$imm3),
+                     IIC_iALUi,
+                     "add", "\t$Rd, $Rm, $imm3",
+                     [(set tGPR:$Rd, (add tGPR:$Rm, imm0_7:$imm3))]>,
+                     Sched<[WriteALU]> {
+    bits<3> imm3;
+    let Inst{8-6} = imm3;
+  }
 
-// Add register
-let isCommutable = 1 in
-def tADDrr :                    // A8.6.6 T1
-  T1sIGenEncode<0b01100, (outs tGPR:$Rd), (ins tGPR:$Rn, tGPR:$Rm),
-                IIC_iALUr,
-                "add", "\t$Rd, $Rn, $Rm",
-                [(set tGPR:$Rd, (add tGPR:$Rn, tGPR:$Rm))]>, Sched<[WriteALU]>;
-
-let hasSideEffects = 0 in
-def tADDhirr : T1pIt<(outs GPR:$Rdn), (ins GPR:$Rn, GPR:$Rm), IIC_iALUr,
-                     "add", "\t$Rdn, $Rm", []>,
-               T1Special<{0,0,?,?}>, Sched<[WriteALU]> {
-  // A8.6.6 T2
-  bits<4> Rdn;
-  bits<4> Rm;
-  let Inst{7}   = Rdn{3};
-  let Inst{6-3} = Rm;
-  let Inst{2-0} = Rdn{2-0};
+  def tADDi8 :                    // A8.6.4 T2
+    T1sItGenEncodeImm<{1,1,0,?,?}, (outs tGPR:$Rdn),
+                      (ins tGPR:$Rn, imm0_255:$imm8), IIC_iALUi,
+                      "add", "\t$Rdn, $imm8",
+                      [(set tGPR:$Rdn, (add tGPR:$Rn, imm8_255:$imm8))]>,
+                      Sched<[WriteALU]>;
+
+  // Add register
+  let isCommutable = 1 in
+  def tADDrr :                    // A8.6.6 T1
+    T1sIGenEncode<0b01100, (outs tGPR:$Rd), (ins tGPR:$Rn, tGPR:$Rm),
+                  IIC_iALUr,
+                  "add", "\t$Rd, $Rn, $Rm",
+                  [(set tGPR:$Rd, (add tGPR:$Rn, tGPR:$Rm))]>, Sched<[WriteALU]>;
+
+  let hasSideEffects = 0 in
+  def tADDhirr : T1pIt<(outs GPR:$Rdn), (ins GPR:$Rn, GPR:$Rm), IIC_iALUr,
+                       "add", "\t$Rdn, $Rm", []>,
+                 T1Special<{0,0,?,?}>, Sched<[WriteALU]> {
+    // A8.6.6 T2
+    bits<4> Rdn;
+    bits<4> Rm;
+    let Inst{7}   = Rdn{3};
+    let Inst{6-3} = Rm;
+    let Inst{2-0} = Rdn{2-0};
+  }
 }
 
 // AND register
diff --git a/llvm/lib/Target/ARM/ARMInstrThumb2.td b/llvm/lib/Target/ARM/ARMInstrThumb2.td
index 7d4f27d38aa..4e55e535a1c 100644
--- a/llvm/lib/Target/ARM/ARMInstrThumb2.td
+++ b/llvm/lib/Target/ARM/ARMInstrThumb2.td
@@ -2038,6 +2038,7 @@ def : Thumb2ExtractPat<(add rGPR:$Rn, (and (srl rGPR:$Rm, imm8_or_16:$rot),
 //  Arithmetic Instructions.
 //
 
+let isAdd = 1 in
 defm t2ADD  : T2I_bin_ii12rs<0b000, "add", add, 1>;
 defm t2SUB  : T2I_bin_ii12rs<0b101, "sub", sub>;
 
diff --git a/llvm/lib/Target/Hexagon/HexagonHardwareLoops.cpp b/llvm/lib/Target/Hexagon/HexagonHardwareLoops.cpp
index 930747faa0d..45e61485410 100644
--- a/llvm/lib/Target/Hexagon/HexagonHardwareLoops.cpp
+++ b/llvm/lib/Target/Hexagon/HexagonHardwareLoops.cpp
@@ -411,10 +411,8 @@ bool HexagonHardwareLoops::findInductionRegister(MachineLoop *L,
 
       unsigned PhiOpReg = Phi->getOperand(i).getReg();
       MachineInstr *DI = MRI->getVRegDef(PhiOpReg);
-      unsigned UpdOpc = DI->getOpcode();
-      bool isAdd = (UpdOpc == Hexagon::A2_addi || UpdOpc == Hexagon::A2_addp);
 
-      if (isAdd) {
+      if (DI->getDesc().isAdd()) {
         // If the register operand to the add is the PHI we're looking at, this
         // meets the induction pattern.
         unsigned IndReg = DI->getOperand(1).getReg();
@@ -1592,10 +1590,8 @@ bool HexagonHardwareLoops::fixupInductionVariable(MachineLoop *L) {
 
       unsigned PhiReg = Phi->getOperand(i).getReg();
       MachineInstr *DI = MRI->getVRegDef(PhiReg);
-      unsigned UpdOpc = DI->getOpcode();
-      bool isAdd = (UpdOpc == Hexagon::A2_addi || UpdOpc == Hexagon::A2_addp);
 
-      if (isAdd) {
+      if (DI->getDesc().isAdd()) {
         // If the register operand to the add/sub is the PHI we are looking
         // at, this meets the induction pattern.
         unsigned IndReg = DI->getOperand(1).getReg();
diff --git a/llvm/lib/Target/Hexagon/HexagonInstrInfo.td b/llvm/lib/Target/Hexagon/HexagonInstrInfo.td
index 26e18b9916a..fd2c7a73de5 100644
--- a/llvm/lib/Target/Hexagon/HexagonInstrInfo.td
+++ b/llvm/lib/Target/Hexagon/HexagonInstrInfo.td
@@ -406,7 +406,7 @@ multiclass Addri_Pred<string mnemonic, bit PredNot> {
 let isExtendable = 1, isExtentSigned = 1, InputType = "imm" in
 multiclass Addri_base<string mnemonic, SDNode OpNode> {
   let CextOpcode = mnemonic, BaseOpcode = mnemonic#_ri in {
-    let opExtendable = 2, opExtentBits = 16, isPredicable = 1 in
+    let opExtendable = 2, opExtentBits = 16, isPredicable = 1, isAdd = 1 in
     def A2_#NAME : T_Addri<s16Ext>;
 
     let opExtendable = 3, opExtentBits = 8, isPredicated = 1 in {
@@ -1292,6 +1292,7 @@ class T_ALU64_arith<string mnemonic, bits<3> MajOp, bits<3> MinOp, bit IsSat,
   : T_ALU64_rr<mnemonic, !if(IsSat,":sat",""), 0b0011, MajOp, MinOp, OpsRev,
                IsComm, "">;
 
+let isAdd = 1 in
 def A2_addp : T_ALU64_arith<"add", 0b000, 0b111, 0, 0, 1>;
 def A2_subp : T_ALU64_arith<"sub", 0b001, 0b111, 0, 1, 0>;