[polly] r311692 - Revert "[polly] Fix ScopDetectionDiagnostic test failure caused by r310940"
Tobias Grosser via llvm-commits
llvm-commits at lists.llvm.org
Thu Aug 24 12:47:15 PDT 2017
Author: grosser
Date: Thu Aug 24 12:47:15 2017
New Revision: 311692
URL: http://llvm.org/viewvc/llvm-project?rev=311692&view=rev
Log:
Revert "[polly] Fix ScopDetectionDiagnostic test failure caused by r310940"
This reverts commit 950849ece9bb8fdd2b41e3ec348b9653b4e37df6.
This commit broke various buildbots.
Modified:
polly/trunk/include/polly/ScopDetectionDiagnostic.h
polly/trunk/lib/Analysis/ScopDetection.cpp
polly/trunk/lib/Analysis/ScopDetectionDiagnostic.cpp
polly/trunk/test/ScopDetectionDiagnostics/ReportLoopHasNoExit.ll
Modified: polly/trunk/include/polly/ScopDetectionDiagnostic.h
URL: http://llvm.org/viewvc/llvm-project/polly/trunk/include/polly/ScopDetectionDiagnostic.h?rev=311692&r1=311691&r2=311692&view=diff
==============================================================================
--- polly/trunk/include/polly/ScopDetectionDiagnostic.h (original)
+++ polly/trunk/include/polly/ScopDetectionDiagnostic.h Thu Aug 24 12:47:15 2017
@@ -86,6 +86,7 @@ enum class RejectReasonKind {
LastAffFunc,
LoopBound,
+ LoopHasNoExit,
LoopOnlySomeLatches,
FuncCall,
@@ -563,6 +564,36 @@ public:
/// @name LLVM-RTTI interface
//@{
+ static bool classof(const RejectReason *RR);
+ //@}
+
+ /// @name RejectReason interface
+ //@{
+ virtual std::string getRemarkName() const override;
+ virtual const Value *getRemarkBB() const override;
+ virtual std::string getMessage() const override;
+ virtual const DebugLoc &getDebugLoc() const override;
+ virtual std::string getEndUserMessage() const override;
+ //@}
+};
+
+//===----------------------------------------------------------------------===//
+/// Captures errors when loop has no exit.
+class ReportLoopHasNoExit : public RejectReason {
+ //===--------------------------------------------------------------------===//
+
+ /// The loop that has no exit.
+ Loop *L;
+
+ const DebugLoc Loc;
+
+public:
+ ReportLoopHasNoExit(Loop *L)
+ : RejectReason(RejectReasonKind::LoopHasNoExit), L(L),
+ Loc(L->getStartLoc()) {}
+
+ /// @name LLVM-RTTI interface
+ //@{
static bool classof(const RejectReason *RR);
//@}
Modified: polly/trunk/lib/Analysis/ScopDetection.cpp
URL: http://llvm.org/viewvc/llvm-project/polly/trunk/lib/Analysis/ScopDetection.cpp?rev=311692&r1=311691&r2=311692&view=diff
==============================================================================
--- polly/trunk/lib/Analysis/ScopDetection.cpp (original)
+++ polly/trunk/lib/Analysis/ScopDetection.cpp Thu Aug 24 12:47:15 2017
@@ -1166,6 +1166,17 @@ bool ScopDetection::isValidInstruction(I
return invalid<ReportUnknownInst>(Context, /*Assert=*/true, &Inst);
}
+/// Check whether @p L has exiting blocks.
+///
+/// @param L The loop of interest
+///
+/// @return True if the loop has exiting blocks, false otherwise.
+static bool hasExitingBlocks(Loop *L) {
+ SmallVector<BasicBlock *, 4> ExitingBlocks;
+ L->getExitingBlocks(ExitingBlocks);
+ return !ExitingBlocks.empty();
+}
+
bool ScopDetection::canUseISLTripCount(Loop *L,
DetectionContext &Context) const {
// Ensure the loop has valid exiting blocks as well as latches, otherwise we
@@ -1186,18 +1197,34 @@ bool ScopDetection::isValidLoop(Loop *L,
// Loops that contain part but not all of the blocks of a region cannot be
// handled by the schedule generation. Such loop constructs can happen
// because a region can contain BBs that have no path to the exit block
- // (infinite loops, UnreachableInst).
- // We do not have to verify against infinite loops here -- they are
- // postdominated only by the virtual exit and do not appear in regions.
- // Instead of an infinite loop, a dead end can also be formed by an
- // UnreachableInst. This case is already caught by isErrorBlock().
-
-#ifndef NDEBUG
- // Make sure that the loop has exits (i.e. is not infinite).
- SmallVector<BasicBlock *, 4> ExitingBlocks;
- L->getExitingBlocks(ExitingBlocks);
- assert(!ExitingBlocks.empty() && "Region with an infinite loop found!");
-#endif
+ // (Infinite loops, UnreachableInst), but such blocks are never part of a
+ // loop.
+ //
+ // _______________
+ // | Loop Header | <-----------.
+ // --------------- |
+ // | |
+ // _______________ ______________
+ // | RegionEntry |-----> | RegionExit |----->
+ // --------------- --------------
+ // |
+ // _______________
+ // | EndlessLoop | <--.
+ // --------------- |
+ // | |
+ // \------------/
+ //
+ // In the example above, the loop (LoopHeader,RegionEntry,RegionExit) is
+ // neither entirely contained in the region RegionEntry->RegionExit
+ // (containing RegionEntry,EndlessLoop) nor is the region entirely contained
+ // in the loop.
+ // The block EndlessLoop is contained in the region because Region::contains
+ // tests whether it is not dominated by RegionExit. This is probably to not
+ // having to query the PostdominatorTree. Instead of an endless loop, a dead
+ // end can also be formed by an UnreachableInst. This case is already caught
+ // by isErrorBlock(). We hence only have to reject endless loops here.
+ if (!hasExitingBlocks(L))
+ return invalid<ReportLoopHasNoExit>(Context, /*Assert=*/true, L);
if (canUseISLTripCount(L, Context))
return true;
Modified: polly/trunk/lib/Analysis/ScopDetectionDiagnostic.cpp
URL: http://llvm.org/viewvc/llvm-project/polly/trunk/lib/Analysis/ScopDetectionDiagnostic.cpp?rev=311692&r1=311691&r2=311692&view=diff
==============================================================================
--- polly/trunk/lib/Analysis/ScopDetectionDiagnostic.cpp (original)
+++ polly/trunk/lib/Analysis/ScopDetectionDiagnostic.cpp Thu Aug 24 12:47:15 2017
@@ -60,6 +60,7 @@ llvm::Statistic RejectStatistics[] = {
SCOP_STAT(DifferentElementSize, "Accesses with differing sizes"),
SCOP_STAT(LastAffFunc, ""),
SCOP_STAT(LoopBound, "Uncomputable loop bounds"),
+ SCOP_STAT(LoopHasNoExit, "Loop without exit"),
SCOP_STAT(LoopOnlySomeLatches, "Not all loop latches in scop"),
SCOP_STAT(FuncCall, "Function call with side effects"),
SCOP_STAT(NonSimpleMemoryAccess,
@@ -459,6 +460,29 @@ std::string ReportLoopBound::getEndUserM
}
//===----------------------------------------------------------------------===//
+// ReportLoopHasNoExit.
+
+std::string ReportLoopHasNoExit::getRemarkName() const {
+ return "LoopHasNoExit";
+}
+
+const Value *ReportLoopHasNoExit::getRemarkBB() const { return L->getHeader(); }
+
+std::string ReportLoopHasNoExit::getMessage() const {
+ return "Loop " + L->getHeader()->getName() + " has no exit.";
+}
+
+bool ReportLoopHasNoExit::classof(const RejectReason *RR) {
+ return RR->getKind() == RejectReasonKind::LoopHasNoExit;
+}
+
+const DebugLoc &ReportLoopHasNoExit::getDebugLoc() const { return Loc; }
+
+std::string ReportLoopHasNoExit::getEndUserMessage() const {
+ return "Loop cannot be handled because it has no exit.";
+}
+
+//===----------------------------------------------------------------------===//
// ReportLoopOnlySomeLatches
std::string ReportLoopOnlySomeLatches::getRemarkName() const {
@@ -475,7 +499,7 @@ std::string ReportLoopOnlySomeLatches::g
}
bool ReportLoopOnlySomeLatches::classof(const RejectReason *RR) {
- return RR->getKind() == RejectReasonKind::LoopOnlySomeLatches;
+ return RR->getKind() == RejectReasonKind::LoopHasNoExit;
}
const DebugLoc &ReportLoopOnlySomeLatches::getDebugLoc() const { return Loc; }
Modified: polly/trunk/test/ScopDetectionDiagnostics/ReportLoopHasNoExit.ll
URL: http://llvm.org/viewvc/llvm-project/polly/trunk/test/ScopDetectionDiagnostics/ReportLoopHasNoExit.ll?rev=311692&r1=311691&r2=311692&view=diff
==============================================================================
--- polly/trunk/test/ScopDetectionDiagnostics/ReportLoopHasNoExit.ll (original)
+++ polly/trunk/test/ScopDetectionDiagnostics/ReportLoopHasNoExit.ll Thu Aug 24 12:47:15 2017
@@ -1,7 +1,7 @@
; XFAIL: *
; The test case stopped making sense after r310940 that added infinite loops to
-; the PostDominatorTree. Infinite loops are postdominated only by the virtual
+; the PostDominatorTree. Infinite loops are postdominated ony by the virtual
; root, which causes them not to appear in regions in ScopDetection anymore.
; RUN: opt %loadPolly -pass-remarks-missed="polly-detect" -polly-allow-nonaffine-loops -analyze -polly-detect < %s 2>&1 | FileCheck %s
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