[PGO][PGSO] SizeOpts changes.

Summary:
(Split of off D67120)

SizeOpts/MachineSizeOpts changes for profile guided size optimization.

Reviewers: davidxl

Subscribers: mgorny, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69070

llvm-svn: 375254

2 files changed, 130 insertions, 0 deletions

diff --git a/llvm/unittests/Transforms/Utils/CMakeLists.txt b/llvm/unittests/Transforms/Utils/CMakeLists.txt
index 785b79865dc..bc993a84f02 100644
--- a/llvm/unittests/Transforms/Utils/CMakeLists.txt
+++ b/llvm/unittests/Transforms/Utils/CMakeLists.txt
@@ -14,6 +14,7 @@ add_llvm_unittest(UtilsTests
   FunctionComparatorTest.cpp
   IntegerDivisionTest.cpp
   LocalTest.cpp
+  SizeOptsTest.cpp
   SSAUpdaterBulkTest.cpp
   UnrollLoopTest.cpp
   ValueMapperTest.cpp
diff --git a/llvm/unittests/Transforms/Utils/SizeOptsTest.cpp b/llvm/unittests/Transforms/Utils/SizeOptsTest.cpp
new file mode 100644
index 00000000000..55ca7863575
--- /dev/null
+++ b/llvm/unittests/Transforms/Utils/SizeOptsTest.cpp
@@ -0,0 +1,129 @@
+//===- SizeOptsTest.cpp - SizeOpts unit tests -----------------------------===//
+//
+// 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/SizeOpts.h"
+#include "llvm/Analysis/ProfileSummaryInfo.h"
+#include "llvm/Analysis/BlockFrequencyInfo.h"
+#include "llvm/Analysis/BranchProbabilityInfo.h"
+#include "llvm/Analysis/LoopInfo.h"
+#include "llvm/AsmParser/Parser.h"
+#include "llvm/IR/BasicBlock.h"
+#include "llvm/IR/Dominators.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/FormatVariadic.h"
+#include "llvm/Support/SourceMgr.h"
+#include "gtest/gtest.h"
+
+using namespace llvm;
+
+namespace {
+
+class SizeOptsTest : public testing::Test {
+protected:
+  static const char* IRString;
+  LLVMContext C;
+  std::unique_ptr<Module> M;
+  struct BFIData {
+    std::unique_ptr<DominatorTree> DT;
+    std::unique_ptr<LoopInfo> LI;
+    std::unique_ptr<BranchProbabilityInfo> BPI;
+    std::unique_ptr<BlockFrequencyInfo> BFI;
+    BFIData(Function &F) {
+      DT.reset(new DominatorTree(F));
+      LI.reset(new LoopInfo(*DT));
+      BPI.reset(new BranchProbabilityInfo(F, *LI));
+      BFI.reset(new BlockFrequencyInfo(F, *BPI, *LI));
+    }
+    BlockFrequencyInfo *get() { return BFI.get(); }
+  };
+
+  void SetUp() override {
+    SMDiagnostic Err;
+    M = parseAssemblyString(IRString, Err, C);
+  }
+};
+
+TEST_F(SizeOptsTest, Test) {
+  Function *F = M->getFunction("f");
+  Function *G = M->getFunction("g");
+  Function *H = M->getFunction("h");
+
+  ProfileSummaryInfo PSI(*M.get());
+  BFIData BFID_F(*F);
+  BFIData BFID_G(*G);
+  BFIData BFID_H(*H);
+  BlockFrequencyInfo *BFI_F = BFID_F.get();
+  BlockFrequencyInfo *BFI_G = BFID_G.get();
+  BlockFrequencyInfo *BFI_H = BFID_H.get();
+  BasicBlock &BB0 = F->getEntryBlock();
+  BasicBlock *BB1 = BB0.getTerminator()->getSuccessor(0);
+  BasicBlock *BB2 = BB0.getTerminator()->getSuccessor(1);
+  BasicBlock *BB3 = BB1->getSingleSuccessor();
+
+  EXPECT_TRUE(PSI.hasProfileSummary());
+  EXPECT_FALSE(shouldOptimizeForSize(F, &PSI, BFI_F));
+  EXPECT_TRUE(shouldOptimizeForSize(G, &PSI, BFI_G));
+  EXPECT_FALSE(shouldOptimizeForSize(H, &PSI, BFI_H));
+  EXPECT_FALSE(shouldOptimizeForSize(&BB0, &PSI, BFI_F));
+  EXPECT_FALSE(shouldOptimizeForSize(BB1, &PSI, BFI_F));
+  EXPECT_TRUE(shouldOptimizeForSize(BB2, &PSI, BFI_F));
+  EXPECT_FALSE(shouldOptimizeForSize(BB3, &PSI, BFI_F));
+}
+
+const char* SizeOptsTest::IRString = R"IR(
+  define i32 @g(i32 %x) !prof !14 {
+    ret i32 0
+  }
+
+  define i32 @h(i32 %x) !prof !15 {
+    ret i32 0
+  }
+
+  define i32 @f(i32 %x) !prof !16 {
+  bb0:
+    %y1 = icmp eq i32 %x, 0
+    br i1 %y1, label %bb1, label %bb2, !prof !17
+
+  bb1:                                              ; preds = %bb0
+    %z1 = call i32 @g(i32 %x)
+    br label %bb3
+
+  bb2:                                              ; preds = %bb0
+    %z2 = call i32 @h(i32 %x)
+    br label %bb3
+
+  bb3:                                              ; preds = %bb2, %bb1
+    %y2 = phi i32 [ 0, %bb1 ], [ 1, %bb2 ]
+    ret i32 %y2
+  }
+
+  !llvm.module.flags = !{!0}
+
+  !0 = !{i32 1, !"ProfileSummary", !1}
+  !1 = !{!2, !3, !4, !5, !6, !7, !8, !9}
+  !2 = !{!"ProfileFormat", !"InstrProf"}
+  !3 = !{!"TotalCount", i64 10000}
+  !4 = !{!"MaxCount", i64 10}
+  !5 = !{!"MaxInternalCount", i64 1}
+  !6 = !{!"MaxFunctionCount", i64 1000}
+  !7 = !{!"NumCounts", i64 3}
+  !8 = !{!"NumFunctions", i64 3}
+  !9 = !{!"DetailedSummary", !10}
+  !10 = !{!11, !12, !13}
+  !11 = !{i32 10000, i64 1000, i32 1}
+  !12 = !{i32 999000, i64 300, i32 3}
+  !13 = !{i32 999999, i64 5, i32 10}
+  !14 = !{!"function_entry_count", i64 1}
+  !15 = !{!"function_entry_count", i64 100}
+  !16 = !{!"function_entry_count", i64 400}
+  !17 = !{!"branch_weights", i32 100, i32 1}
+)IR";
+
+} // end anonymous namespace