[mlir][SCF] Remove scf-bufferize pass

Author: matthias-springer

mlir/docs/Bufferization.md

@@ -579,7 +579,6 @@ The code, slightly simplified and annotated, is reproduced here:
   // Partial bufferization passes.
   pm.addPass(createTensorConstantBufferizePass());
   pm.addNestedPass<func::FuncOp>(createTCPBufferizePass()); // Bufferizes the downstream `tcp` dialect.
-  pm.addNestedPass<func::FuncOp>(createSCFBufferizePass());
   pm.addNestedPass<func::FuncOp>(createLinalgBufferizePass());
   pm.addNestedPass<func::FuncOp>(createTensorBufferizePass());
   pm.addPass(createFuncBufferizePass());
@@ -596,7 +595,7 @@ must be module passes because they make changes to the top-level module.
 
 The bulk of the bufferization work is done by the function passes. Most of these
 passes are provided as part of the upstream MLIR distribution and bufferize
-their respective dialects (e.g. `scf-bufferize` bufferizes the `scf` dialect).
+their respective dialects (e.g. `abc-bufferize` bufferizes the `abc` dialect).
 The `tcp-bufferize` pass is an exception -- it is a partial bufferization pass
 used to bufferize the downstream `tcp` dialect, and fits in perfectly with all
 the other passes provided upstream.
@@ -694,20 +693,6 @@ which helps with this in general.
 
 ### Other partial bufferization examples
 
--   `scf-bufferize`
-    ([code](https://github.com/llvm/llvm-project/blob/bc8acf2ce8ad6e8c9b1d97b2e02d3f4ad26e1d9d/mlir/lib/Dialect/SCF/Transforms/Bufferize.cpp#L1),
-    [test](https://github.com/llvm/llvm-project/blob/bc8acf2ce8ad6e8c9b1d97b2e02d3f4ad26e1d9d/mlir/test/Dialect/SCF/bufferize.mlir#L1))
-
-    -   Bufferizes ops from the `scf` dialect.
-    -   This is an example of how to bufferize ops that implement
-        `RegionBranchOpInterface` (that is, they use regions to represent
-        control flow).
-    -   The bulk of the work is done by
-        `lib/Dialect/SCF/Transforms/StructuralTypeConversions.cpp`
-        ([code](https://github.com/llvm/llvm-project/blob/daaaed6bb89044ac58a23f1bb1ccdd12342a5a58/mlir/lib/Dialect/SCF/Transforms/StructuralTypeConversions.cpp#L1)),
-        which is well-commented and covers how to correctly convert ops that
-        contain regions.
-
 -   `func-bufferize`
     ([code](https://github.com/llvm/llvm-project/blob/2f5715dc78328215d51d5664c72c632a6dac1046/mlir/lib/Dialect/Func/Transforms/FuncBufferize.cpp#L1),
     [test](https://github.com/llvm/llvm-project/blob/2f5715dc78328215d51d5664c72c632a6dac1046/mlir/test/Dialect/Func/func-bufferize.mlir#L1))

mlir/include/mlir/Dialect/SCF/Transforms/Passes.h

@@ -20,9 +20,6 @@ namespace mlir {
 #define GEN_PASS_DECL
 #include "mlir/Dialect/SCF/Transforms/Passes.h.inc"
 
-/// Creates a pass that bufferizes the SCF dialect.
-std::unique_ptr<Pass> createSCFBufferizePass();
-
 /// Creates a pass that specializes for loop for unrolling and
 /// vectorization.
 std::unique_ptr<Pass> createForLoopSpecializationPass();

mlir/include/mlir/Dialect/SCF/Transforms/Passes.td

@@ -11,13 +11,6 @@
 
 include "mlir/Pass/PassBase.td"
 
-def SCFBufferize : Pass<"scf-bufferize"> {
-  let summary = "Bufferize the scf dialect.";
-  let constructor = "mlir::createSCFBufferizePass()";
-  let dependentDialects = ["bufferization::BufferizationDialect",
-                           "memref::MemRefDialect"];
-}
-
 // Note: Making these canonicalization patterns would require a dependency
 // of the SCF dialect on the Affine/Tensor/MemRef dialects or vice versa.
 def SCFForLoopCanonicalization

mlir/lib/Dialect/SCF/Transforms/Bufferize.cpp

@@ -1,7 +1,6 @@
 add_mlir_dialect_library(MLIRSCFTransforms
   BufferDeallocationOpInterfaceImpl.cpp
   BufferizableOpInterfaceImpl.cpp
-  Bufferize.cpp
   ForallToFor.cpp
   ForallToParallel.cpp
   ForToWhile.cpp