[polly] r251227 - ScopDetection: Update DetectionContextMap accordingly

[Tobias Grosser via llvm-commits]

Author: grosser
Date: Sun Oct 25 05:55:35 2015
New Revision: 251227

URL: http://llvm.org/viewvc/llvm-project?rev=251227&view=rev
Log:
ScopDetection: Update DetectionContextMap accordingly

When verifying if a scop is still valid we rerun all analysis, but did not
update DetectionContextMap. This change ensures that information, e.g. about
non-affine regions, is correctly updated

Added:
    polly/trunk/test/Isl/CodeGen/multiple-scops-in-a-row.ll
Modified:
    polly/trunk/include/polly/ScopDetection.h
    polly/trunk/lib/Analysis/ScopDetection.cpp

Modified: polly/trunk/include/polly/ScopDetection.h
URL: http://llvm.org/viewvc/llvm-project/polly/trunk/include/polly/ScopDetection.h?rev=251227&r1=251226&r2=251227&view=diff
==============================================================================
--- polly/trunk/include/polly/ScopDetection.h (original)
+++ polly/trunk/include/polly/ScopDetection.h Sun Oct 25 05:55:35 2015
@@ -201,7 +201,7 @@ private:
 
   /// @brief Map to remember detection contexts for valid regions.
   using DetectionContextMapTy = DenseMap<const Region *, DetectionContext>;
-  DetectionContextMapTy DetectionContextMap;
+  mutable DetectionContextMapTy DetectionContextMap;
 
   // Remember a list of errors for every region.
   mutable RejectLogsContainer RejectLogs;

Modified: polly/trunk/lib/Analysis/ScopDetection.cpp
URL: http://llvm.org/viewvc/llvm-project/polly/trunk/lib/Analysis/ScopDetection.cpp?rev=251227&r1=251226&r2=251227&view=diff
==============================================================================
--- polly/trunk/lib/Analysis/ScopDetection.cpp (original)
+++ polly/trunk/lib/Analysis/ScopDetection.cpp Sun Oct 25 05:55:35 2015
@@ -254,7 +254,11 @@ bool ScopDetection::isMaxRegionInScop(co
     return false;
 
   if (Verify) {
-    DetectionContext Context(const_cast<Region &>(R), *AA, false /*verifying*/);
+    DetectionContextMap.erase(&R);
+    const auto &It = DetectionContextMap.insert(
+        std::make_pair(&R, DetectionContext(const_cast<Region &>(R), *AA,
+                                            false /*verifying*/)));
+    DetectionContext &Context = It.first->second;
     return isValidRegion(Context);
   }
 

Added: polly/trunk/test/Isl/CodeGen/multiple-scops-in-a-row.ll
URL: http://llvm.org/viewvc/llvm-project/polly/trunk/test/Isl/CodeGen/multiple-scops-in-a-row.ll?rev=251227&view=auto
==============================================================================
--- polly/trunk/test/Isl/CodeGen/multiple-scops-in-a-row.ll (added)
+++ polly/trunk/test/Isl/CodeGen/multiple-scops-in-a-row.ll Sun Oct 25 05:55:35 2015
@@ -0,0 +1,51 @@
+; RUN: opt %loadPolly -S -polly-codegen < %s | FileCheck %s
+
+; This test case has two scops in a row. When code generating the first scop,
+; the second scop is invalidated. This test case verifies that we do not crash
+; due to incorrectly assuming the second scop is still valid.
+
+; We explicitly check here that the second scop is not code generated. Later
+; improvements may make this possible (e.g., Polly gaining support for
+; parameteric conditional expressions or a changed code generation order).
+; However, in case this happens, we want to ensure this test case is been
+; reasoned about and updated accordingly.
+
+; CHECK: polly.start:
+; CHECK-NOT: polly.start:
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+
+define void @hoge(i8* %arg) {
+bb:
+  br label %bb1
+
+bb1:                                              ; preds = %bb
+  %tmp = getelementptr inbounds i8, i8* %arg, i64 5
+  %tmp2 = getelementptr inbounds i8, i8* %arg, i64 6
+  br i1 false, label %bb3, label %bb4
+
+bb3:                                              ; preds = %bb1
+  br label %bb4
+
+bb4:                                              ; preds = %bb3, %bb1
+  %tmp5 = icmp eq i32 0, 1
+  br label %bb6
+
+bb6:                                              ; preds = %bb4
+  br i1 undef, label %bb7, label %bb8
+
+bb7:                                              ; preds = %bb6
+  unreachable
+
+bb8:                                              ; preds = %bb6
+  br i1 %tmp5, label %bb9, label %bb10
+
+bb9:                                              ; preds = %bb8
+  br label %bb11
+
+bb10:                                             ; preds = %bb8
+  br label %bb11
+
+bb11:                                             ; preds = %bb10, %bb9
+  ret void
+}