unittests/CodeGen/GlobalISel/CSETest.cpp

   1 //===- CSETest.cpp -----------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "GISelMITest.h"
  10 #include "llvm/CodeGen/GlobalISel/CSEMIRBuilder.h"
  11
  12 namespace {
  13
  14 TEST_F(GISelMITest, TestCSE) {
  15   if (!TM)
  16     return;
  17
  18   LLT s16{LLT::scalar(16)};
  19   LLT s32{LLT::scalar(32)};
  20   auto MIBInput = B.buildInstr(TargetOpcode::G_TRUNC, {s16}, {Copies[0]});
  21   auto MIBInput1 = B.buildInstr(TargetOpcode::G_TRUNC, {s16}, {Copies[1]});
  22   auto MIBAdd = B.buildInstr(TargetOpcode::G_ADD, {s16}, {MIBInput, MIBInput});
  23   GISelCSEInfo CSEInfo;
  24   CSEInfo.setCSEConfig(make_unique<CSEConfigFull>());
  25   CSEInfo.analyze(*MF);
  26   B.setCSEInfo(&CSEInfo);
  27   CSEMIRBuilder CSEB(B.getState());
  28
  29   CSEB.setInsertPt(*EntryMBB, EntryMBB->begin());
  30   unsigned AddReg = MRI->createGenericVirtualRegister(s16);
  31   auto MIBAddCopy =
  32       CSEB.buildInstr(TargetOpcode::G_ADD, {AddReg}, {MIBInput, MIBInput});
  33   EXPECT_EQ(MIBAddCopy->getOpcode(), TargetOpcode::COPY);
  34   auto MIBAdd2 =
  35       CSEB.buildInstr(TargetOpcode::G_ADD, {s16}, {MIBInput, MIBInput});
  36   EXPECT_TRUE(&*MIBAdd == &*MIBAdd2);
  37   auto MIBAdd4 =
  38       CSEB.buildInstr(TargetOpcode::G_ADD, {s16}, {MIBInput, MIBInput});
  39   EXPECT_TRUE(&*MIBAdd == &*MIBAdd4);
  40   auto MIBAdd5 =
  41       CSEB.buildInstr(TargetOpcode::G_ADD, {s16}, {MIBInput, MIBInput1});
  42   EXPECT_TRUE(&*MIBAdd != &*MIBAdd5);
  43
  44   // Try building G_CONSTANTS.
  45   auto MIBCst = CSEB.buildConstant(s32, 0);
  46   auto MIBCst1 = CSEB.buildConstant(s32, 0);
  47   EXPECT_TRUE(&*MIBCst == &*MIBCst1);
  48   // Try the CFing of BinaryOps.
  49   auto MIBCF1 = CSEB.buildInstr(TargetOpcode::G_ADD, {s32}, {MIBCst, MIBCst});
  50   EXPECT_TRUE(&*MIBCF1 == &*MIBCst);
  51
  52   // Try out building FCONSTANTs.
  53   auto MIBFP0 = CSEB.buildFConstant(s32, 1.0);
  54   auto MIBFP0_1 = CSEB.buildFConstant(s32, 1.0);
  55   EXPECT_TRUE(&*MIBFP0 == &*MIBFP0_1);
  56   CSEInfo.print();
  57
  58   // Make sure buildConstant with a vector type doesn't crash, and the elements
  59   // CSE.
  60   auto Splat0 = CSEB.buildConstant(LLT::vector(2, s32), 0);
  61   EXPECT_EQ(TargetOpcode::G_BUILD_VECTOR, Splat0->getOpcode());
  62   EXPECT_EQ(Splat0->getOperand(1).getReg(), Splat0->getOperand(2).getReg());
  63   EXPECT_EQ(&*MIBCst, MRI->getVRegDef(Splat0->getOperand(1).getReg()));
  64
  65   auto FSplat = CSEB.buildFConstant(LLT::vector(2, s32), 1.0);
  66   EXPECT_EQ(TargetOpcode::G_BUILD_VECTOR, FSplat->getOpcode());
  67   EXPECT_EQ(FSplat->getOperand(1).getReg(), FSplat->getOperand(2).getReg());
  68   EXPECT_EQ(&*MIBFP0, MRI->getVRegDef(FSplat->getOperand(1).getReg()));
  69
  70   // Check G_UNMERGE_VALUES
  71   auto MIBUnmerge = CSEB.buildUnmerge({s32, s32}, Copies[0]);
  72   auto MIBUnmerge2 = CSEB.buildUnmerge({s32, s32}, Copies[0]);
  73   EXPECT_TRUE(&*MIBUnmerge == &*MIBUnmerge2);
  74 }
  75
  76 TEST_F(GISelMITest, TestCSEConstantConfig) {
  77   if (!TM)
  78     return;
  79
  80   LLT s16{LLT::scalar(16)};
  81   auto MIBInput = B.buildInstr(TargetOpcode::G_TRUNC, {s16}, {Copies[0]});
  82   auto MIBAdd = B.buildInstr(TargetOpcode::G_ADD, {s16}, {MIBInput, MIBInput});
  83   auto MIBZero = B.buildConstant(s16, 0);
  84   GISelCSEInfo CSEInfo;
  85   CSEInfo.setCSEConfig(make_unique<CSEConfigConstantOnly>());
  86   CSEInfo.analyze(*MF);
  87   B.setCSEInfo(&CSEInfo);
  88   CSEMIRBuilder CSEB(B.getState());
  89   CSEB.setInsertPt(*EntryMBB, EntryMBB->begin());
  90   auto MIBAdd1 =
  91       CSEB.buildInstr(TargetOpcode::G_ADD, {s16}, {MIBInput, MIBInput});
  92   // We should CSE constants only. Adds should not be CSEd.
  93   EXPECT_TRUE(MIBAdd1->getOpcode() != TargetOpcode::COPY);
  94   EXPECT_TRUE(&*MIBAdd1 != &*MIBAdd);
  95   // We should CSE constant.
  96   auto MIBZeroTmp = CSEB.buildConstant(s16, 0);
  97   EXPECT_TRUE(&*MIBZero == &*MIBZeroTmp);
  98 }
  99 } // namespace