[Mlir-commits] [mlir] [MLIR] VectorEmulateNarrowType to support loading of unaligned vectors (PR #113411)

[llvmlistbot at llvm.org]

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@@ -0,0 +1,67 @@
+// RUN: mlir-opt --test-emulate-narrow-int="arith-compute-bitwidth=1 memref-load-bitwidth=8" --cse --split-input-file %s | FileCheck %s
+
+func.func @vector_load_i2(%arg1: index, %arg2: index) -> vector<3x3xi2> {
+    %0 = memref.alloc() : memref<3x3xi2>
+    %c0 = arith.constant 0 : index
+    %c2 = arith.constant 2 : index
+    %cst = arith.constant dense<0> : vector<3x3xi2>
+    %1 = vector.load %0[%c2, %c0] : memref<3x3xi2>, vector<3xi2>
+    %2 = vector.insert %1, %cst [0] : vector<3xi2> into vector<3x3xi2>
+    return %2 : vector<3x3xi2>
+}
+
+// CHECK: func @vector_load_i2
+// CHECK: %[[ALLOC:.+]] = memref.alloc() : memref<3xi8>
+// CHECK: %[[INDEX:.+]] = arith.constant 1 : index
+// CHECK: %[[VEC:.+]] = vector.load %[[ALLOC]][%[[INDEX]]] : memref<3xi8>, vector<2xi8>
+// CHECK: %[[VEC_I2:.+]] = vector.bitcast %[[VEC]] : vector<2xi8> to vector<8xi2>
+// CHECK: %[[EXCTRACT:.+]] = vector.extract_strided_slice %[[VEC_I2]] {offsets = [2], sizes = [3], strides = [1]} : vector<8xi2> to vector<3xi2>
+
+//-----
+
+func.func @vector_transfer_read_i2() -> vector<3xi2> {
----------------
lialan wrote:

if we do `[%c0, %c2]` in this case, the emitted code piece is like this:
```
%c0 = arith.constant 0 : index
%0 = vector.load %alloc[%c0] : memref<3xi8>, vector<2xi8>
%1 = vector.bitcast %0 : vector<2xi8> to vector<8xi2>
%2 = vector.extract_strided_slice %1 {offsets = [2], sizes = [3], strides = [1]} : vector<8xi2> to vector<3xi2>
```

Note that the byte load offset changed from 1 to 0. The indices are seen as a linearized one. 


https://github.com/llvm/llvm-project/pull/113411