fixup! [loop count assumptions] convert loop iteration metadata to as…

…sumptions
Xilinx · Nov 28, 2024 · 9863dd9 · 9863dd9
1 parent deff215
commit 9863dd9
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Showing 2 changed files with 57 additions and 4 deletions.
diff --git a/llvm/lib/Transforms/Utils/LoopIterCountAssumptions.cpp b/llvm/lib/Transforms/Utils/LoopIterCountAssumptions.cpp
@@ -107,6 +107,11 @@ Value *recursivlyCloneInBB(Value *Op, BasicBlock &BB, ValueToValueMapTy &VMap) {
                       << *Op << "\n");
     return nullptr;
   }
+  if (!I->isSafeToRemove()) {
+    LLVM_DEBUG(dbgs() << "Instruction is not Safe to clone: Aborting! " << *Op
+                      << "\n");
+    return nullptr;
+  }
 
   auto NewI = I->clone();
   NewI->insertBefore(&BB.front());

diff --git a/llvm/test/Transforms/Util/loop-iter-count-assumptions.ll b/llvm/test/Transforms/Util/loop-iter-count-assumptions.ll
@@ -998,7 +998,8 @@ for.body:                                         ; preds = %for.cond
 }
 
 
-; int &n; for (int i =0 ; i < n + 1; i++)
+; int &n
+; for (int i =0 ; i < n + 1; i++)
 define dso_local void @incrementOffsetOneSigned(ptr noalias %ptr, ptr nonnull align 32 dereferenceable(288)  %n) #0 {
 ; CHECK-LABEL: @incrementOffsetOneSigned(
 ; CHECK-NEXT:  entry:
@@ -1048,7 +1049,8 @@ for.body:                                         ; preds = %for.cond
   br label %for.cond, !llvm.loop !6
 }
 
-; unsigned &n; for (unsigned i =0 ; i < n + 1; i++)
+; unsigned &n
+; for (unsigned i =0 ; i < n + 1; i++)
 define dso_local void @incrementOffsetOneUnsigned(ptr noalias %ptr, ptr nonnull align 32 dereferenceable(288)  %n) #0 {
 ; CHECK-LABEL: @incrementOffsetOneUnsigned(
 ; CHECK-NEXT:  entry:
@@ -1098,7 +1100,8 @@ for.body:                                         ; preds = %for.cond
   br label %for.cond, !llvm.loop !6
 }
 
-; int &n; for (int i =0 ; i < n - 1; i++)
+; int &n
+; for (int i =0 ; i < n - 1; i++)
 define dso_local void @incrementOffsetNegOneSigned(ptr noalias %ptr, ptr nonnull align 32 dereferenceable(288)  %n) #0 {
 ; CHECK-LABEL: @incrementOffsetNegOneSigned(
 ; CHECK-NEXT:  entry:
@@ -1148,7 +1151,8 @@ for.body:                                         ; preds = %for.cond
   br label %for.cond, !llvm.loop !6
 }
 
-; unsigned &n; for (unsigned i =0 ; i < n - 1; i++)
+; unsigned &n
+; for (unsigned i =0 ; i < n - 1; i++)
 define dso_local void @incrementOffsetNegOneUnsigned(ptr noalias %ptr, ptr nonnull align 32 dereferenceable(288)  %n) #0 {
 ; CHECK-LABEL: @incrementOffsetNegOneUnsigned(
 ; CHECK-NEXT:  entry:
@@ -1198,6 +1202,50 @@ for.body:                                         ; preds = %for.cond
   br label %for.cond, !llvm.loop !6
 }
 
+; do not insert Assumption if a call instruction should be cloned, since the
+; result could be non-deterministic
+; Function Attrs: mustprogress noinline nounwind optnone
+define dso_local void @abortOnCallClone(ptr %ptr, i32 noundef %n, i32 noundef %m) #0 {
+; CHECK-LABEL: @abortOnCallClone(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    br label [[FOR_COND:%.*]]
+; CHECK:       for.cond:
+; CHECK-NEXT:    [[I_0:%.*]] = phi i32 [ [[M:%.*]], [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_BODY:%.*]] ]
+; CHECK-NEXT:    [[N_0:%.*]] = call i32 @calcN(i32 [[N:%.*]])
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[I_0]], [[N_0]]
+; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[FOR_COND_CLEANUP:%.*]]
+; CHECK:       for.cond.cleanup:
+; CHECK-NEXT:    ret void
+; CHECK:       for.body:
+; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i32, ptr [[PTR:%.*]], i32 [[I_0]]
+; CHECK-NEXT:    [[TMP0:%.*]] = load i32, ptr [[ARRAYIDX]], align 4
+; CHECK-NEXT:    [[ADD:%.*]] = add nsw i32 [[TMP0]], 8
+; CHECK-NEXT:    store i32 [[ADD]], ptr [[ARRAYIDX]], align 4
+; CHECK-NEXT:    [[INC]] = add nsw i32 [[I_0]], 1
+; CHECK-NEXT:    br label [[FOR_COND]], !llvm.loop [[LOOP0]]
+;
+entry:
+  br label %for.cond
+
+for.cond:                                         ; preds = %for.body, %entry
+  %i.0 = phi i32 [ %m, %entry ], [ %inc, %for.body ]
+  %n.0 = call i32 @calcN(i32 %n)
+  %cmp = icmp slt i32 %i.0, %n.0
+  br i1 %cmp, label %for.body, label %for.cond.cleanup
+
+for.cond.cleanup:                                 ; preds = %for.cond
+  ret void
+
+for.body:                                         ; preds = %for.cond
+  %arrayidx = getelementptr inbounds i32, ptr %ptr, i32 %i.0
+  %0 = load i32, ptr %arrayidx, align 4
+  %add = add nsw i32 %0, 8
+  store i32 %add, ptr %arrayidx, align 4
+  %inc = add nsw i32 %i.0, 1
+  br label %for.cond, !llvm.loop !6
+}
+
+declare dso_local i32 @calcN(i32 noundef %n)
 
 !3 = distinct !{!3, !11, !7, !9}
 !6 = distinct !{!6, !7, !8, !9}