| //===- LoopRotationUtilsTest.cpp - Unit tests for LoopRotation utility ----===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/Transforms/Utils/LoopRotationUtils.h" |
| #include "llvm/Analysis/AssumptionCache.h" |
| #include "llvm/Analysis/InstructionSimplify.h" |
| #include "llvm/Analysis/LoopInfo.h" |
| #include "llvm/Analysis/ScalarEvolution.h" |
| #include "llvm/Analysis/TargetLibraryInfo.h" |
| #include "llvm/Analysis/TargetTransformInfo.h" |
| #include "llvm/AsmParser/Parser.h" |
| #include "llvm/IR/Dominators.h" |
| #include "llvm/IR/LLVMContext.h" |
| #include "llvm/Support/SourceMgr.h" |
| #include "gtest/gtest.h" |
| |
| using namespace llvm; |
| |
| static std::unique_ptr<Module> parseIR(LLVMContext &C, const char *IR) { |
| SMDiagnostic Err; |
| std::unique_ptr<Module> Mod = parseAssemblyString(IR, Err, C); |
| if (!Mod) |
| Err.print("LoopRotationUtilsTest", errs()); |
| return Mod; |
| } |
| |
| /// This test contains multi-deopt-exits pattern that might allow loop rotation |
| /// to trigger multiple times if multiple rotations are enabled. |
| /// At least one rotation should be performed, no matter what loop rotation settings are. |
| TEST(LoopRotate, MultiDeoptExit) { |
| LLVMContext C; |
| |
| std::unique_ptr<Module> M = parseIR( |
| C, |
| R"( |
| declare i32 @llvm.experimental.deoptimize.i32(...) |
| |
| define i32 @test(i32 * nonnull %a, i64 %x) { |
| entry: |
| br label %for.cond1 |
| |
| for.cond1: |
| %idx = phi i64 [ 0, %entry ], [ %idx.next, %for.tail ] |
| %sum = phi i32 [ 0, %entry ], [ %sum.next, %for.tail ] |
| %a.idx = getelementptr inbounds i32, i32 *%a, i64 %idx |
| %val.a.idx = load i32, i32* %a.idx, align 4 |
| %zero.check = icmp eq i32 %val.a.idx, 0 |
| br i1 %zero.check, label %deopt.exit, label %for.cond2 |
| |
| for.cond2: |
| %for.check = icmp ult i64 %idx, %x |
| br i1 %for.check, label %for.body, label %return |
| |
| for.body: |
| br label %for.tail |
| |
| for.tail: |
| %sum.next = add i32 %sum, %val.a.idx |
| %idx.next = add nuw nsw i64 %idx, 1 |
| br label %for.cond1 |
| |
| return: |
| ret i32 %sum |
| |
| deopt.exit: |
| %deopt.val = call i32(...) @llvm.experimental.deoptimize.i32() [ "deopt"(i32 %val.a.idx) ] |
| ret i32 %deopt.val |
| })" |
| ); |
| |
| auto *F = M->getFunction("test"); |
| DominatorTree DT(*F); |
| LoopInfo LI(DT); |
| AssumptionCache AC(*F); |
| TargetTransformInfo TTI(M->getDataLayout()); |
| TargetLibraryInfoImpl TLII; |
| TargetLibraryInfo TLI(TLII); |
| ScalarEvolution SE(*F, TLI, AC, DT, LI); |
| SimplifyQuery SQ(M->getDataLayout()); |
| |
| Loop *L = *LI.begin(); |
| |
| bool ret = LoopRotation(L, &LI, &TTI, |
| &AC, &DT, |
| &SE, nullptr, |
| SQ, true, -1, false); |
| EXPECT_TRUE(ret); |
| } |
| |
| /// Checking a special case of multi-deopt exit loop that can not perform |
| /// required amount of rotations due to the desired header containing |
| /// non-duplicatable code. |
| /// Similar to MultiDeoptExit test this one should do at least one rotation and |
| /// pass no matter what loop rotation settings are. |
| TEST(LoopRotate, MultiDeoptExit_Nondup) { |
| LLVMContext C; |
| |
| std::unique_ptr<Module> M = parseIR( |
| C, |
| R"( |
| ; Rotation should be done once, attempted twice. |
| ; Second time fails due to non-duplicatable header. |
| |
| declare i32 @llvm.experimental.deoptimize.i32(...) |
| |
| declare void @nondup() |
| |
| define i32 @test_nondup(i32 * nonnull %a, i64 %x) { |
| entry: |
| br label %for.cond1 |
| |
| for.cond1: |
| %idx = phi i64 [ 0, %entry ], [ %idx.next, %for.tail ] |
| %sum = phi i32 [ 0, %entry ], [ %sum.next, %for.tail ] |
| %a.idx = getelementptr inbounds i32, i32 *%a, i64 %idx |
| %val.a.idx = load i32, i32* %a.idx, align 4 |
| %zero.check = icmp eq i32 %val.a.idx, 0 |
| br i1 %zero.check, label %deopt.exit, label %for.cond2 |
| |
| for.cond2: |
| call void @nondup() noduplicate |
| %for.check = icmp ult i64 %idx, %x |
| br i1 %for.check, label %for.body, label %return |
| |
| for.body: |
| br label %for.tail |
| |
| for.tail: |
| %sum.next = add i32 %sum, %val.a.idx |
| %idx.next = add nuw nsw i64 %idx, 1 |
| br label %for.cond1 |
| |
| return: |
| ret i32 %sum |
| |
| deopt.exit: |
| %deopt.val = call i32(...) @llvm.experimental.deoptimize.i32() [ "deopt"(i32 %val.a.idx) ] |
| ret i32 %deopt.val |
| })" |
| ); |
| |
| auto *F = M->getFunction("test_nondup"); |
| DominatorTree DT(*F); |
| LoopInfo LI(DT); |
| AssumptionCache AC(*F); |
| TargetTransformInfo TTI(M->getDataLayout()); |
| TargetLibraryInfoImpl TLII; |
| TargetLibraryInfo TLI(TLII); |
| ScalarEvolution SE(*F, TLI, AC, DT, LI); |
| SimplifyQuery SQ(M->getDataLayout()); |
| |
| Loop *L = *LI.begin(); |
| |
| bool ret = LoopRotation(L, &LI, &TTI, |
| &AC, &DT, |
| &SE, nullptr, |
| SQ, true, -1, false); |
| /// LoopRotation should properly report "true" as we still perform the first rotation |
| /// so we do change the IR. |
| EXPECT_TRUE(ret); |
| } |