Use getLoopLatch in place of isLoopSimplifyForm
Summary:
Use getLoopLatch in place of isLoopSimplifyForm. we do not need
to know whether the loop has a preheader nor dedicated exits.
Reviewers: hfinkel, sanjoy, atrick, mkuper
Subscribers: mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D28724
llvm-svn: 292078
diff --git a/llvm/unittests/Analysis/LoopInfoTest.cpp b/llvm/unittests/Analysis/LoopInfoTest.cpp
new file mode 100644
index 0000000..3832d88
--- /dev/null
+++ b/llvm/unittests/Analysis/LoopInfoTest.cpp
@@ -0,0 +1,77 @@
+//===- LoopInfoTest.cpp - LoopInfo unit tests -----------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Analysis/LoopInfo.h"
+#include "llvm/AsmParser/Parser.h"
+#include "llvm/IR/Dominators.h"
+#include "llvm/Support/SourceMgr.h"
+#include "gtest/gtest.h"
+
+using namespace llvm;
+
+static std::unique_ptr<Module> makeLLVMModule(LLVMContext &Context,
+ const char *ModuleStr) {
+ SMDiagnostic Err;
+ return parseAssemblyString(ModuleStr, Err, Context);
+}
+
+// This tests that for a loop with a single latch, we get the loop id from
+// its only latch, even in case the loop may not be in a simplified form.
+TEST(LoopInfoTest, LoopWithSingleLatch) {
+ const char *ModuleStr =
+ "target datalayout = \"e-m:o-i64:64-f80:128-n8:16:32:64-S128\"\n"
+ "define void @foo(i32 %n) {\n"
+ "entry:\n"
+ " br i1 undef, label %for.cond, label %for.end\n"
+ "for.cond:\n"
+ " %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.inc ]\n"
+ " %cmp = icmp slt i32 %i.0, %n\n"
+ " br i1 %cmp, label %for.inc, label %for.end\n"
+ "for.inc:\n"
+ " %inc = add nsw i32 %i.0, 1\n"
+ " br label %for.cond, !llvm.loop !0\n"
+ "for.end:\n"
+ " ret void\n"
+ "}\n"
+ "!0 = distinct !{!0, !1}\n"
+ "!1 = !{!\"llvm.loop.distribute.enable\", i1 true}\n";
+
+ // Parse the module.
+ LLVMContext Context;
+ std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr);
+
+ // Build the dominator tree and loop info.
+ DominatorTree DT;
+ DT.recalculate(*M->begin());
+ LoopInfo LI;
+ LI.analyze(DT);
+
+
+ Function &F = *M->begin();
+ Function::iterator FI = F.begin();
+ FI++; // First basic block is entry - skip it.
+ BasicBlock *Header = &*FI++;
+ assert(Header->getName() == "for.cond");
+ Loop *L = LI.getLoopFor(Header);
+
+ // This loop is not in simplified form.
+ EXPECT_FALSE(L->isLoopSimplifyForm());
+
+ // Analyze the loop metadata id.
+ bool loopIDFoundAndSet = false;
+ // Try to get and set the metadata id for the loop.
+ if (MDNode *D = L->getLoopID()) {
+ L->setLoopID(D);
+ loopIDFoundAndSet = true;
+ }
+
+ // We must have successfully found and set the loop id in the
+ // only latch the loop has.
+ EXPECT_TRUE(loopIDFoundAndSet);
+}