[llvm] r328364 - [Hexagon] Boost profit for word-mask immediates, reduce for others

Krzysztof Parzyszek via llvm-commits llvm-commits at lists.llvm.org
Fri Mar 23 13:11:01 PDT 2018


Author: kparzysz
Date: Fri Mar 23 13:11:00 2018
New Revision: 328364

URL: http://llvm.org/viewvc/llvm-project?rev=328364&view=rev
Log:
[Hexagon] Boost profit for word-mask immediates, reduce for others

This avoids unnecessary splitting due to uninteresting immediates.

Added:
    llvm/trunk/test/CodeGen/Hexagon/sdr-nosplit1.ll
    llvm/trunk/test/CodeGen/Hexagon/sdr-reg-profit.ll
Modified:
    llvm/trunk/lib/Target/Hexagon/HexagonSplitDouble.cpp

Modified: llvm/trunk/lib/Target/Hexagon/HexagonSplitDouble.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/Hexagon/HexagonSplitDouble.cpp?rev=328364&r1=328363&r2=328364&view=diff
==============================================================================
--- llvm/trunk/lib/Target/Hexagon/HexagonSplitDouble.cpp (original)
+++ llvm/trunk/lib/Target/Hexagon/HexagonSplitDouble.cpp Fri Mar 23 13:11:00 2018
@@ -55,6 +55,8 @@ static cl::opt<int> MaxHSDR("max-hsdr",
     cl::desc("Maximum number of split partitions"));
 static cl::opt<bool> MemRefsFixed("hsdr-no-mem", cl::Hidden, cl::init(true),
     cl::desc("Do not split loads or stores"));
+  static cl::opt<bool> SplitAll("hsdr-split-all", cl::Hidden, cl::init(false),
+      cl::desc("Split all partitions"));
 
 namespace {
 
@@ -97,6 +99,7 @@ namespace {
     bool isFixedInstr(const MachineInstr *MI) const;
     void partitionRegisters(UUSetMap &P2Rs);
     int32_t profit(const MachineInstr *MI) const;
+    int32_t profit(unsigned Reg) const;
     bool isProfitable(const USet &Part, LoopRegMap &IRM) const;
 
     void collectIndRegsForLoop(const MachineLoop *L, USet &Rs);
@@ -306,13 +309,10 @@ void HexagonSplitDoubleRegs::partitionRe
 
 static inline int32_t profitImm(unsigned Lo, unsigned Hi) {
   int32_t P = 0;
-  bool LoZ1 = false, HiZ1 = false;
   if (Lo == 0 || Lo == 0xFFFFFFFF)
-    P += 10, LoZ1 = true;
+    P += 10;
   if (Hi == 0 || Hi == 0xFFFFFFFF)
-    P += 10, HiZ1 = true;
-  if (!LoZ1 && !HiZ1 && Lo == Hi)
-    P += 3;
+    P += 10;
   return P;
 }
 
@@ -368,8 +368,11 @@ int32_t HexagonSplitDoubleRegs::profit(c
 
     case Hexagon::A2_andp:
     case Hexagon::A2_orp:
-    case Hexagon::A2_xorp:
-      return 1;
+    case Hexagon::A2_xorp: {
+      unsigned Rs = MI->getOperand(1).getReg();
+      unsigned Rt = MI->getOperand(2).getReg();
+      return profit(Rs) + profit(Rt);
+    }
 
     case Hexagon::S2_asl_i_p_or: {
       unsigned S = MI->getOperand(3).getImm();
@@ -393,6 +396,25 @@ int32_t HexagonSplitDoubleRegs::profit(c
   return 0;
 }
 
+int32_t HexagonSplitDoubleRegs::profit(unsigned Reg) const {
+  assert(TargetRegisterInfo::isVirtualRegister(Reg));
+
+  const MachineInstr *DefI = MRI->getVRegDef(Reg);
+  switch (DefI->getOpcode()) {
+    case Hexagon::A2_tfrpi:
+    case Hexagon::CONST64:
+    case Hexagon::A2_combineii:
+    case Hexagon::A4_combineii:
+    case Hexagon::A4_combineri:
+    case Hexagon::A4_combineir:
+    case Hexagon::A2_combinew:
+      return profit(DefI);
+    default:
+      break;
+  }
+  return 0;
+}
+
 bool HexagonSplitDoubleRegs::isProfitable(const USet &Part, LoopRegMap &IRM)
       const {
   unsigned FixedNum = 0, LoopPhiNum = 0;
@@ -443,6 +465,8 @@ bool HexagonSplitDoubleRegs::isProfitabl
     TotalP -= 20*LoopPhiNum;
 
   DEBUG(dbgs() << "Partition profit: " << TotalP << '\n');
+  if (SplitAll)
+    return true;
   return TotalP > 0;
 }
 
@@ -1160,12 +1184,12 @@ bool HexagonSplitDoubleRegs::splitPartit
 }
 
 bool HexagonSplitDoubleRegs::runOnMachineFunction(MachineFunction &MF) {
-  DEBUG(dbgs() << "Splitting double registers in function: "
-        << MF.getName() << '\n');
-
   if (skipFunction(MF.getFunction()))
     return false;
 
+  DEBUG(dbgs() << "Splitting double registers in function: "
+        << MF.getName() << '\n');
+
   auto &ST = MF.getSubtarget<HexagonSubtarget>();
   TRI = ST.getRegisterInfo();
   TII = ST.getInstrInfo();

Added: llvm/trunk/test/CodeGen/Hexagon/sdr-nosplit1.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/Hexagon/sdr-nosplit1.ll?rev=328364&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/Hexagon/sdr-nosplit1.ll (added)
+++ llvm/trunk/test/CodeGen/Hexagon/sdr-nosplit1.ll Fri Mar 23 13:11:00 2018
@@ -0,0 +1,42 @@
+; RUN: llc -march=hexagon < %s | FileCheck %s
+;
+; Make sure that the A2_andp is not split.
+;
+; CHECK: loop0([[LOOP:.LBB[_0-9]+]],{{.*}})
+; CHECK: [[LOOP]]:
+; CHECK: and(r{{[0-9]+}}:{{[0-9]+}},r{{[0-9]+}}:{{[0-9]+}})
+
+target triple = "hexagon"
+
+define void @fred(i64 %a0, i64 %a1, i64 %a2, i64* nocapture %a3, i32 %a4) local_unnamed_addr #0 {
+b5:
+  %v6 = icmp sgt i32 %a4, 0
+  br i1 %v6, label %b7, label %b20
+
+b7:                                               ; preds = %b7, %b5
+  %v8 = phi i64* [ %v16, %b7 ], [ %a3, %b5 ]
+  %v9 = phi i32 [ %v18, %b7 ], [ 0, %b5 ]
+  %v10 = phi i64 [ %v17, %b7 ], [ %a0, %b5 ]
+  %v11 = tail call i64 @llvm.hexagon.A2.andp(i64 %v10, i64 1085102592571150095)
+  %v12 = tail call i32 @llvm.hexagon.A2.vcmpbgtu(i64 %a1, i64 %v11)
+  %v13 = tail call i64 @llvm.hexagon.A2.vsubub(i64 %v11, i64 %a1)
+  %v14 = and i32 %v12, 255
+  %v15 = tail call i64 @llvm.hexagon.C2.vmux(i32 %v14, i64 %a2, i64 %v13)
+  store i64 %v15, i64* %v8, align 8
+  %v16 = getelementptr i64, i64* %v8, i32 1
+  %v17 = load i64, i64* %v16, align 8
+  %v18 = add nuw nsw i32 %v9, 1
+  %v19 = icmp eq i32 %v18, %a4
+  br i1 %v19, label %b20, label %b7
+
+b20:                                              ; preds = %b7, %b5
+  ret void
+}
+
+declare i64 @llvm.hexagon.A2.andp(i64, i64) #1
+declare i32 @llvm.hexagon.A2.vcmpbgtu(i64, i64) #1
+declare i64 @llvm.hexagon.A2.vsubub(i64, i64) #1
+declare i64 @llvm.hexagon.C2.vmux(i32, i64, i64) #1
+
+attributes #0 = { nounwind "target-cpu"="hexagonv60" }
+attributes #1 = { nounwind readnone }

Added: llvm/trunk/test/CodeGen/Hexagon/sdr-reg-profit.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/Hexagon/sdr-reg-profit.ll?rev=328364&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/Hexagon/sdr-reg-profit.ll (added)
+++ llvm/trunk/test/CodeGen/Hexagon/sdr-reg-profit.ll Fri Mar 23 13:11:00 2018
@@ -0,0 +1,103 @@
+; RUN: llc -march=hexagon < %s | FileCheck %s
+;
+; Split all andp/orp instructions (by boosting the profitability of their
+; operands, which happen to be word masks).
+; This should result in a loop with two packets, but we don't generate
+; post-incremented loads, so we end up with 3 packets.
+
+; CHECK-LABEL: fred
+; CHECK: loop0([[LOOP:.LBB[0-9_]+]],
+; CHECK: [[LOOP]]:
+; CHECK: {
+; CHECK: {
+; Make sure that the 3rd packet only has an add in it.
+; CHECK: {
+; CHECK:  r[[REG:[0-9]+]] = add(r[[REG]],#16)
+; CHECK-NOT: {
+; CHECK: }{{[ \t]*}}:endloop0
+
+target triple = "hexagon"
+
+define i32 @fred(i32 %a0, i64* nocapture readonly %a1) local_unnamed_addr #0 {
+b2:
+  %v3 = bitcast i64* %a1 to i32*
+  %v4 = getelementptr inbounds i32, i32* %v3, i32 1
+  %v5 = load i32, i32* %v3, align 4
+  %v6 = load i32, i32* %v4, align 4
+  %v7 = zext i32 %a0 to i64
+  br label %b8
+
+b8:                                               ; preds = %b8, %b2
+  %v9 = phi i32 [ %v6, %b2 ], [ %v49, %b8 ]
+  %v10 = phi i32 [ %v5, %b2 ], [ %v48, %b8 ]
+  %v11 = phi i32 [ 2, %b2 ], [ %v45, %b8 ]
+  %v12 = phi i64 [ 0, %b2 ], [ %v46, %b8 ]
+  %v13 = phi i64 [ 0, %b2 ], [ %v47, %b8 ]
+  %v14 = phi i32 [ 0, %b2 ], [ %v33, %b8 ]
+  %v15 = phi i32 [ 0, %b2 ], [ %v40, %b8 ]
+  %v16 = zext i32 %v10 to i64
+  %v17 = or i64 %v12, %v16
+  %v18 = tail call i64 @llvm.hexagon.S4.vxsubaddhr(i64 %v17, i64 %v7)
+  %v19 = zext i32 %v9 to i64
+  %v20 = or i64 %v13, %v19
+  %v21 = tail call i64 @llvm.hexagon.S4.vxsubaddhr(i64 %v20, i64 %v7)
+  %v22 = getelementptr inbounds i32, i32* %v3, i32 %v11
+  %v23 = load i32, i32* %v22, align 4
+  %v24 = or i32 %v11, 1
+  %v25 = getelementptr inbounds i32, i32* %v3, i32 %v24
+  %v26 = load i32, i32* %v25, align 4
+  %v27 = zext i32 %v14 to i64
+  %v28 = shl nuw i64 %v27, 32
+  %v29 = zext i32 %v23 to i64
+  %v30 = or i64 %v28, %v29
+  %v31 = tail call i64 @llvm.hexagon.S4.vxaddsubhr(i64 %v30, i64 %v7)
+  %v32 = lshr i64 %v31, 32
+  %v33 = trunc i64 %v32 to i32
+  %v34 = zext i32 %v15 to i64
+  %v35 = shl nuw i64 %v34, 32
+  %v36 = zext i32 %v26 to i64
+  %v37 = or i64 %v35, %v36
+  %v38 = tail call i64 @llvm.hexagon.S4.vxaddsubhr(i64 %v37, i64 %v7)
+  %v39 = lshr i64 %v38, 32
+  %v40 = trunc i64 %v39 to i32
+  %v41 = add nuw nsw i32 %v11, 2
+  %v42 = getelementptr inbounds i32, i32* %v3, i32 %v41
+  %v43 = add nuw nsw i32 %v11, 3
+  %v44 = getelementptr inbounds i32, i32* %v3, i32 %v43
+  %v45 = add nuw nsw i32 %v11, 4
+  %v46 = and i64 %v18, -4294967296
+  %v47 = and i64 %v21, -4294967296
+  %v48 = load i32, i32* %v42, align 4
+  %v49 = load i32, i32* %v44, align 4
+  %v50 = icmp ult i32 %v45, 30
+  br i1 %v50, label %b8, label %b51
+
+b51:                                              ; preds = %b8
+  %v52 = zext i32 %v48 to i64
+  %v53 = or i64 %v46, %v52
+  %v54 = add i64 %v53, %v7
+  %v55 = lshr i64 %v54, 32
+  %v56 = trunc i64 %v55 to i32
+  %v57 = zext i32 %v49 to i64
+  %v58 = or i64 %v47, %v57
+  %v59 = add i64 %v58, %v7
+  %v60 = lshr i64 %v59, 32
+  %v61 = trunc i64 %v60 to i32
+  %v62 = tail call i64 @llvm.hexagon.A2.combinew(i32 %v33, i32 %v56)
+  %v63 = lshr i64 %v62, 32
+  %v64 = trunc i64 %v63 to i32
+  %v65 = tail call i64 @llvm.hexagon.A2.combinew(i32 %v40, i32 %v61)
+  %v66 = lshr i64 %v65, 32
+  %v67 = trunc i64 %v66 to i32
+  %v68 = tail call i64 @llvm.hexagon.A2.combinew(i32 %v67, i32 %v64)
+  %v69 = lshr i64 %v68, 32
+  %v70 = trunc i64 %v69 to i32
+  ret i32 %v70
+}
+
+declare i64 @llvm.hexagon.S4.vxsubaddhr(i64, i64) #1
+declare i64 @llvm.hexagon.S4.vxaddsubhr(i64, i64) #1
+declare i64 @llvm.hexagon.A2.combinew(i32, i32) #1
+
+attributes #0 = { nounwind readonly "target-cpu"="hexagonv60" }
+attributes #1 = { nounwind readnone }




More information about the llvm-commits mailing list