[mlir][TOSA] Do not access erased operation

[matthias-springer]

This commit fixes two occurrences where an erased op was accessed at a later point of time. That won't work anymore in a One-Shot Dialect Conversion and triggers a use-after-free sanitizer error.

After the One-Shot Dialect Conversion refactoring, a ConversionPatternRewriter will behave more like a normal PatternRewriter.

[llvmbot]

@llvm/pr-subscribers-mlir

@llvm/pr-subscribers-mlir-linalg

Author: Matthias Springer (matthias-springer)

Changes

Do not access the erased MaxPool2dOp operation in the lowering pattern. That won't work anymore in a One-Shot Dialect Conversion and triggers a use-after-free sanitizer error.

After the One-Shot Dialect Conversion refactoring, a ConversionPatternRewriter will behave more like a normal PatternRewriter.

---

Full diff: https://github.com/llvm/llvm-project/pull/148374.diff

1 Files Affected:

• (modified) mlir/lib/Conversion/TosaToLinalg/TosaToLinalgNamed.cpp (+6-6)

diff --git a/mlir/lib/Conversion/TosaToLinalg/TosaToLinalgNamed.cpp b/mlir/lib/Conversion/TosaToLinalg/TosaToLinalgNamed.cpp
index c1f40dcbd5ca0..4f62dc13e33b9 100644
--- a/mlir/lib/Conversion/TosaToLinalg/TosaToLinalgNamed.cpp
+++ b/mlir/lib/Conversion/TosaToLinalg/TosaToLinalgNamed.cpp
@@ -808,6 +808,7 @@ class MaxPool2dConverter : public OpConversionPattern<tosa::MaxPool2dOp> {
         dilationAttr);
 
     rewriter.setInsertionPointAfter(op);
+    auto nanMode = op.getNanMode();
     rewriter.replaceOp(op, resultOp);
 
     // NaN propagation has no meaning for non floating point types.
@@ -821,11 +822,10 @@ class MaxPool2dConverter : public OpConversionPattern<tosa::MaxPool2dOp> {
     // we've already produced a named op we will just take its body and modify
     // it to include the appropriate checks. If the current value is NaN the
     // old value of pool will be taken otherwise we use the result.
-    if (const auto nanMode = op.getNanMode(); nanMode == "IGNORE") {
+    if (nanMode == "IGNORE") {
       auto genericOp = rewriter.create<linalg::GenericOp>(
-          op->getLoc(), resultOp.getType(0), resultOp.getInputs(),
-          resultOp.getOutputs(), resultOp.getIndexingMapsArray(),
-          resultOp.getIteratorTypesArray(),
+          loc, resultOp.getType(0), resultOp.getInputs(), resultOp.getOutputs(),
+          resultOp.getIndexingMapsArray(), resultOp.getIteratorTypesArray(),
           [&](OpBuilder &opBuilder, Location loc, ValueRange blockArgs) {
             IRMapping map;
             auto oldBlock = resultOp.getRegion().begin();
@@ -834,10 +834,10 @@ class MaxPool2dConverter : public OpConversionPattern<tosa::MaxPool2dOp> {
             map.map(oldArgs, blockArgs);
             auto *newOp = opBuilder.clone(oldMaxOp, map);
             Value isNaN = opBuilder.create<arith::CmpFOp>(
-                op->getLoc(), arith::CmpFPredicate::UNO, blockArgs.front(),
+                loc, arith::CmpFPredicate::UNO, blockArgs.front(),
                 blockArgs.front());
             auto selectOp = opBuilder.create<arith::SelectOp>(
-                op->getLoc(), isNaN, blockArgs.back(), newOp->getResult(0));
+                loc, isNaN, blockArgs.back(), newOp->getResult(0));
             opBuilder.create<linalg::YieldOp>(loc, selectOp.getResult());
           });
       rewriter.replaceOp(resultOp, genericOp);