[ARM] Add missing patterns for DSP muls

Using a PatLeaf for sext_16_node allowed matching smulbb and smlabb
instructions once the operands had been sign extended. But we also
need to use sext_inreg operands along with sext_16_node to catch a
few more cases that enable use to remove the unnecessary sxth.

Differential Revision: https://reviews.llvm.org/D55992

llvm-svn: 350613

2 files changed, 60 insertions, 80 deletions

diff --git a/llvm/lib/Target/ARM/ARMInstrInfo.td b/llvm/lib/Target/ARM/ARMInstrInfo.td
index 4f42601a894..46bdeba6bbd 100644
--- a/llvm/lib/Target/ARM/ARMInstrInfo.td
+++ b/llvm/lib/Target/ARM/ARMInstrInfo.td
@@ -426,24 +426,22 @@ def imm16_31 : ImmLeaf<i32, [{
 
 // sext_16_node predicate - True if the SDNode is sign-extended 16 or more bits.
 def sext_16_node : PatLeaf<(i32 GPR:$a), [{
-  if (CurDAG->ComputeNumSignBits(SDValue(N,0)) >= 17)
-    return true;
-
-  if (N->getOpcode() != ISD::SRA)
-    return false;
-  if (N->getOperand(0).getOpcode() != ISD::SHL)
-    return false;
-
-  auto *ShiftVal = dyn_cast<ConstantSDNode>(N->getOperand(1));
-  if (!ShiftVal || ShiftVal->getZExtValue() != 16)
-    return false;
+  return CurDAG->ComputeNumSignBits(SDValue(N,0)) >= 17;
+}]>;
 
-  ShiftVal = dyn_cast<ConstantSDNode>(N->getOperand(0)->getOperand(1));
-  if (!ShiftVal || ShiftVal->getZExtValue() != 16)
-    return false;
+def sext_bottom_16 : PatFrag<(ops node:$a),
+                             (sext_inreg node:$a, i16)>;
+def sext_top_16 : PatFrag<(ops node:$a),
+                          (i32 (sra node:$a, (i32 16)))>;
 
-  return true;
-}]>;
+def bb_mul : PatFrag<(ops node:$a, node:$b),
+                     (mul (sext_bottom_16 node:$a), (sext_bottom_16 node:$b))>;
+def bt_mul : PatFrag<(ops node:$a, node:$b),
+                     (mul (sext_bottom_16 node:$a), (sra node:$b, (i32 16)))>;
+def tb_mul : PatFrag<(ops node:$a, node:$b),
+                     (mul (sra node:$a, (i32 16)), (sext_bottom_16 node:$b))>;
+def tt_mul : PatFrag<(ops node:$a, node:$b),
+                     (mul (sra node:$a, (i32 16)), (sra node:$b, (i32 16)))>;
 
 /// Split a 32-bit immediate into two 16 bit parts.
 def hi16 : SDNodeXForm<imm, [{
@@ -4241,29 +4239,25 @@ def SMMLSR : AMul2Ia <0b0111010, 0b1111, (outs GPR:$Rd),
 multiclass AI_smul<string opc> {
   def BB : AMulxyI<0b0001011, 0b00, (outs GPR:$Rd), (ins GPR:$Rn, GPR:$Rm),
               IIC_iMUL16, !strconcat(opc, "bb"), "\t$Rd, $Rn, $Rm",
-              [(set GPR:$Rd, (mul (sext_inreg GPR:$Rn, i16),
-                                      (sext_inreg GPR:$Rm, i16)))]>,
+              [(set GPR:$Rd, (bb_mul GPR:$Rn, GPR:$Rm))]>,
            Requires<[IsARM, HasV5TE]>,
            Sched<[WriteMUL16, ReadMUL, ReadMUL]>;
 
   def BT : AMulxyI<0b0001011, 0b10, (outs GPR:$Rd), (ins GPR:$Rn, GPR:$Rm),
               IIC_iMUL16, !strconcat(opc, "bt"), "\t$Rd, $Rn, $Rm",
-              [(set GPR:$Rd, (mul (sext_inreg GPR:$Rn, i16),
-                                      (sra GPR:$Rm, (i32 16))))]>,
+              [(set GPR:$Rd, (bt_mul GPR:$Rn, GPR:$Rm))]>,
            Requires<[IsARM, HasV5TE]>,
            Sched<[WriteMUL16, ReadMUL, ReadMUL]>;
 
   def TB : AMulxyI<0b0001011, 0b01, (outs GPR:$Rd), (ins GPR:$Rn, GPR:$Rm),
               IIC_iMUL16, !strconcat(opc, "tb"), "\t$Rd, $Rn, $Rm",
-              [(set GPR:$Rd, (mul (sra GPR:$Rn, (i32 16)),
-                                      (sext_inreg GPR:$Rm, i16)))]>,
+              [(set GPR:$Rd, (tb_mul GPR:$Rn, GPR:$Rm))]>,
            Requires<[IsARM, HasV5TE]>,
            Sched<[WriteMUL16, ReadMUL, ReadMUL]>;
 
   def TT : AMulxyI<0b0001011, 0b11, (outs GPR:$Rd), (ins GPR:$Rn, GPR:$Rm),
               IIC_iMUL16, !strconcat(opc, "tt"), "\t$Rd, $Rn, $Rm",
-              [(set GPR:$Rd, (mul (sra GPR:$Rn, (i32 16)),
-                                      (sra GPR:$Rm, (i32 16))))]>,
+              [(set GPR:$Rd, (tt_mul GPR:$Rn, GPR:$Rm))]>,
             Requires<[IsARM, HasV5TE]>,
            Sched<[WriteMUL16, ReadMUL, ReadMUL]>;
 
@@ -4287,35 +4281,31 @@ multiclass AI_smla<string opc> {
               (ins GPRnopc:$Rn, GPRnopc:$Rm, GPR:$Ra),
               IIC_iMAC16, !strconcat(opc, "bb"), "\t$Rd, $Rn, $Rm, $Ra",
               [(set GPRnopc:$Rd, (add GPR:$Ra,
-                               (mul (sext_inreg GPRnopc:$Rn, i16),
-                                       (sext_inreg GPRnopc:$Rm, i16))))]>,
+                                      (bb_mul GPRnopc:$Rn, GPRnopc:$Rm)))]>,
            Requires<[IsARM, HasV5TE, UseMulOps]>,
            Sched<[WriteMAC16, ReadMUL, ReadMUL, ReadMAC]>;
 
   def BT : AMulxyIa<0b0001000, 0b10, (outs GPRnopc:$Rd),
               (ins GPRnopc:$Rn, GPRnopc:$Rm, GPR:$Ra),
               IIC_iMAC16, !strconcat(opc, "bt"), "\t$Rd, $Rn, $Rm, $Ra",
-              [(set GPRnopc:$Rd,
-                    (add GPR:$Ra, (mul (sext_inreg GPRnopc:$Rn, i16),
-                                          (sra GPRnopc:$Rm, (i32 16)))))]>,
+              [(set GPRnopc:$Rd, (add GPR:$Ra,
+                                      (bt_mul GPRnopc:$Rn, GPRnopc:$Rm)))]>,
            Requires<[IsARM, HasV5TE, UseMulOps]>,
            Sched<[WriteMAC16, ReadMUL, ReadMUL, ReadMAC]>;
 
   def TB : AMulxyIa<0b0001000, 0b01, (outs GPRnopc:$Rd),
               (ins GPRnopc:$Rn, GPRnopc:$Rm, GPR:$Ra),
               IIC_iMAC16, !strconcat(opc, "tb"), "\t$Rd, $Rn, $Rm, $Ra",
-              [(set GPRnopc:$Rd,
-                    (add GPR:$Ra, (mul (sra GPRnopc:$Rn, (i32 16)),
-                                          (sext_inreg GPRnopc:$Rm, i16))))]>,
+              [(set GPRnopc:$Rd, (add GPR:$Ra,
+                                      (tb_mul GPRnopc:$Rn, GPRnopc:$Rm)))]>,
            Requires<[IsARM, HasV5TE, UseMulOps]>,
            Sched<[WriteMAC16, ReadMUL, ReadMUL, ReadMAC]>;
 
   def TT : AMulxyIa<0b0001000, 0b11, (outs GPRnopc:$Rd),
               (ins GPRnopc:$Rn, GPRnopc:$Rm, GPR:$Ra),
               IIC_iMAC16, !strconcat(opc, "tt"), "\t$Rd, $Rn, $Rm, $Ra",
-             [(set GPRnopc:$Rd,
-                   (add GPR:$Ra, (mul (sra GPRnopc:$Rn, (i32 16)),
-                                         (sra GPRnopc:$Rm, (i32 16)))))]>,
+             [(set GPRnopc:$Rd, (add GPR:$Ra,
+                                     (tt_mul GPRnopc:$Rn, GPRnopc:$Rm)))]>,
             Requires<[IsARM, HasV5TE, UseMulOps]>,
             Sched<[WriteMAC16, ReadMUL, ReadMUL, ReadMAC]>;
 
@@ -5816,26 +5806,21 @@ def : ARMPat<(extloadi16 addrmodepc:$addr), (PICLDRH addrmodepc:$addr)>;
 
 // smul* and smla*
 def : ARMV5TEPat<(mul sext_16_node:$a, sext_16_node:$b),
-                 (SMULBB GPR:$a, GPR:$b)>,
-      Sched<[WriteMUL32, ReadMUL, ReadMUL]>;
-def : ARMV5TEPat<(mul sext_16_node:$a, (sra GPR:$b, (i32 16))),
-                 (SMULBT GPR:$a, GPR:$b)>,
-      Sched<[WriteMUL32, ReadMUL, ReadMUL]>;
-def : ARMV5TEPat<(mul (sra GPR:$a, (i32 16)), sext_16_node:$b),
-                (SMULTB GPR:$a, GPR:$b)>,
-      Sched<[WriteMUL32, ReadMUL, ReadMUL]>;
-def : ARMV5MOPat<(add GPR:$acc,
-                      (mul sext_16_node:$a, sext_16_node:$b)),
-                 (SMLABB GPR:$a, GPR:$b, GPR:$acc)>,
-      Sched<[WriteMUL32, ReadMUL, ReadMUL]>;
-def : ARMV5MOPat<(add GPR:$acc,
-                      (mul sext_16_node:$a, (sra GPR:$b, (i32 16)))),
-                 (SMLABT GPR:$a, GPR:$b, GPR:$acc)>,
-      Sched<[WriteMUL32, ReadMUL, ReadMUL]>;
-def : ARMV5MOPat<(add GPR:$acc,
-                      (mul (sra GPR:$a, (i32 16)), sext_16_node:$b)),
-                 (SMLATB GPR:$a, GPR:$b, GPR:$acc)>,
-      Sched<[WriteMUL32, ReadMUL, ReadMUL]>;
+                 (SMULBB GPR:$a, GPR:$b)>;
+def : ARMV5TEPat<(mul sext_16_node:$a, (sext_bottom_16 GPR:$b)),
+                 (SMULBB GPR:$a, GPR:$b)>;
+def : ARMV5TEPat<(mul sext_16_node:$a, (sext_top_16 GPR:$b)),
+                 (SMULBT GPR:$a, GPR:$b)>;
+def : ARMV5TEPat<(mul (sext_top_16 GPR:$a), sext_16_node:$b),
+                 (SMULTB GPR:$a, GPR:$b)>;
+def : ARMV5MOPat<(add GPR:$acc, (mul sext_16_node:$a, sext_16_node:$b)),
+                 (SMLABB GPR:$a, GPR:$b, GPR:$acc)>;
+def : ARMV5MOPat<(add GPR:$acc, (mul sext_16_node:$a, (sext_bottom_16 GPR:$b))),
+                 (SMLABB GPR:$a, GPR:$b, GPR:$acc)>;
+def : ARMV5MOPat<(add GPR:$acc, (mul sext_16_node:$a, (sext_top_16 GPR:$b))),
+                 (SMLABT GPR:$a, GPR:$b, GPR:$acc)>;
+def : ARMV5MOPat<(add GPR:$acc, (mul (sext_top_16 GPR:$a), sext_16_node:$b)),
+                 (SMLATB GPR:$a, GPR:$b, GPR:$acc)>;
 
 def : ARMV5TEPat<(int_arm_smulbb GPR:$a, GPR:$b),
                  (SMULBB GPR:$a, GPR:$b)>;
diff --git a/llvm/lib/Target/ARM/ARMInstrThumb2.td b/llvm/lib/Target/ARM/ARMInstrThumb2.td
index 18a7ee4c419..7a6673b49d5 100644
--- a/llvm/lib/Target/ARM/ARMInstrThumb2.td
+++ b/llvm/lib/Target/ARM/ARMInstrThumb2.td
@@ -2732,28 +2732,25 @@ class T2ThreeRegSMUL<bits<3> op22_20, bits<2> op5_4, string opc,
 }
 
 def t2SMULBB : T2ThreeRegSMUL<0b001, 0b00, "smulbb",
-             [(set rGPR:$Rd, (mul (sext_inreg rGPR:$Rn, i16),
-                                   (sext_inreg rGPR:$Rm, i16)))]>;
+             [(set rGPR:$Rd, (bb_mul rGPR:$Rn, rGPR:$Rm))]>;
 def t2SMULBT : T2ThreeRegSMUL<0b001, 0b01, "smulbt",
-             [(set rGPR:$Rd, (mul (sext_inreg rGPR:$Rn, i16),
-                                   (sra rGPR:$Rm, (i32 16))))]>;
+             [(set rGPR:$Rd, (bt_mul rGPR:$Rn, rGPR:$Rm))]>;
 def t2SMULTB : T2ThreeRegSMUL<0b001, 0b10, "smultb",
-             [(set rGPR:$Rd, (mul (sra rGPR:$Rn, (i32 16)),
-                                   (sext_inreg rGPR:$Rm, i16)))]>;
+             [(set rGPR:$Rd, (tb_mul rGPR:$Rn, rGPR:$Rm))]>;
 def t2SMULTT : T2ThreeRegSMUL<0b001, 0b11, "smultt",
-             [(set rGPR:$Rd, (mul (sra rGPR:$Rn, (i32 16)),
-                                   (sra rGPR:$Rm, (i32 16))))]>;
+             [(set rGPR:$Rd, (tt_mul rGPR:$Rn, rGPR:$Rm))]>;
 def t2SMULWB : T2ThreeRegSMUL<0b011, 0b00, "smulwb",
              [(set rGPR:$Rd, (ARMsmulwb rGPR:$Rn, rGPR:$Rm))]>;
 def t2SMULWT : T2ThreeRegSMUL<0b011, 0b01, "smulwt",
              [(set rGPR:$Rd, (ARMsmulwt rGPR:$Rn, rGPR:$Rm))]>;
 
-def : Thumb2DSPPat<(mul sext_16_node:$Rm, sext_16_node:$Rn),
-                   (t2SMULBB rGPR:$Rm, rGPR:$Rn)>;
-def : Thumb2DSPPat<(mul sext_16_node:$Rn, (sra rGPR:$Rm, (i32 16))),
+def : Thumb2DSPPat<(mul sext_16_node:$Rn, (sext_bottom_16 rGPR:$Rm)),
+                   (t2SMULBB rGPR:$Rn, rGPR:$Rm)>;
+def : Thumb2DSPPat<(mul sext_16_node:$Rn, (sext_top_16 rGPR:$Rm)),
                    (t2SMULBT rGPR:$Rn, rGPR:$Rm)>;
-def : Thumb2DSPPat<(mul (sra rGPR:$Rn, (i32 16)), sext_16_node:$Rm),
+def : Thumb2DSPPat<(mul (sext_top_16 rGPR:$Rn), sext_16_node:$Rm),
                    (t2SMULTB rGPR:$Rn, rGPR:$Rm)>;
+
 def : Thumb2DSPPat<(int_arm_smulbb rGPR:$Rn, rGPR:$Rm),
                    (t2SMULBB rGPR:$Rn, rGPR:$Rm)>;
 def : Thumb2DSPPat<(int_arm_smulbt rGPR:$Rn, rGPR:$Rm),
@@ -2781,18 +2778,13 @@ class T2FourRegSMLA<bits<3> op22_20, bits<2> op5_4, string opc,
 }
 
 def t2SMLABB : T2FourRegSMLA<0b001, 0b00, "smlabb",
-             [(set rGPR:$Rd, (add rGPR:$Ra,
-                               (mul (sext_inreg rGPR:$Rn, i16),
-                                     (sext_inreg rGPR:$Rm, i16))))]>;
+             [(set rGPR:$Rd, (add rGPR:$Ra, (bb_mul rGPR:$Rn, rGPR:$Rm)))]>;
 def t2SMLABT : T2FourRegSMLA<0b001, 0b01, "smlabt",
-             [(set rGPR:$Rd, (add rGPR:$Ra, (mul (sext_inreg rGPR:$Rn, i16),
-                                                 (sra rGPR:$Rm, (i32 16)))))]>;
+             [(set rGPR:$Rd, (add rGPR:$Ra, (bt_mul rGPR:$Rn, rGPR:$Rm)))]>;
 def t2SMLATB : T2FourRegSMLA<0b001, 0b10, "smlatb",
-             [(set rGPR:$Rd, (add rGPR:$Ra, (mul (sra rGPR:$Rn, (i32 16)),
-                                                (sext_inreg rGPR:$Rm, i16))))]>;
+             [(set rGPR:$Rd, (add rGPR:$Ra, (tb_mul rGPR:$Rn, rGPR:$Rm)))]>;
 def t2SMLATT : T2FourRegSMLA<0b001, 0b11, "smlatt",
-             [(set rGPR:$Rd, (add rGPR:$Ra, (mul (sra rGPR:$Rn, (i32 16)),
-                                                 (sra rGPR:$Rm, (i32 16)))))]>;
+             [(set rGPR:$Rd, (add rGPR:$Ra, (tt_mul rGPR:$Rn, rGPR:$Rm)))]>;
 def t2SMLAWB : T2FourRegSMLA<0b011, 0b00, "smlawb",
              [(set rGPR:$Rd, (add rGPR:$Ra, (ARMsmulwb rGPR:$Rn, rGPR:$Rm)))]>;
 def t2SMLAWT : T2FourRegSMLA<0b011, 0b01, "smlawt",
@@ -2800,11 +2792,14 @@ def t2SMLAWT : T2FourRegSMLA<0b011, 0b01, "smlawt",
 
 def : Thumb2DSPMulPat<(add rGPR:$Ra, (mul sext_16_node:$Rn, sext_16_node:$Rm)),
                       (t2SMLABB rGPR:$Rn, rGPR:$Rm, rGPR:$Ra)>;
-def : Thumb2DSPMulPat<(add rGPR:$Ra,
-                        (mul sext_16_node:$Rn, (sra rGPR:$Rm, (i32 16)))),
+def : Thumb2DSPMulPat<(add rGPR:$Ra, (mul sext_16_node:$Rn, 
+                                          (sext_bottom_16 rGPR:$Rm))),
+                      (t2SMLABB rGPR:$Rn, rGPR:$Rm, rGPR:$Ra)>;
+def : Thumb2DSPMulPat<(add rGPR:$Ra, (mul sext_16_node:$Rn,
+                                          (sext_top_16 rGPR:$Rm))),
                       (t2SMLABT rGPR:$Rn, rGPR:$Rm, rGPR:$Ra)>;
-def : Thumb2DSPMulPat<(add rGPR:$Ra,
-                        (mul (sra rGPR:$Rn, (i32 16)), sext_16_node:$Rm)),
+def : Thumb2DSPMulPat<(add rGPR:$Ra, (mul (sext_top_16 rGPR:$Rn),
+                                          sext_16_node:$Rm)),
                       (t2SMLATB rGPR:$Rn, rGPR:$Rm, rGPR:$Ra)>;
 
 def : Thumb2DSPPat<(int_arm_smlabb GPR:$a, GPR:$b, GPR:$acc),