[mlir][EmitC] Fail on memrefs with 0 dims in type conversion

[simon-camp]

This let's the type conversion fail instead of generating invalid array types.

[llvmbot]

@llvm/pr-subscribers-mlir-emitc

@llvm/pr-subscribers-mlir

Author: Simon Camphausen (simon-camp)

Changes

This let's the type conversion fail instead of generating invalid array types.

---

Full diff: https://github.com/llvm/llvm-project/pull/111965.diff

2 Files Affected:

• (modified) mlir/lib/Conversion/MemRefToEmitC/MemRefToEmitC.cpp (+3-1)
• (modified) mlir/test/Conversion/MemRefToEmitC/memref-to-emitc-failed.mlir (+16)

diff --git a/mlir/lib/Conversion/MemRefToEmitC/MemRefToEmitC.cpp b/mlir/lib/Conversion/MemRefToEmitC/MemRefToEmitC.cpp
index 2b7ac4b529cf0d..39532d34f616eb 100644
--- a/mlir/lib/Conversion/MemRefToEmitC/MemRefToEmitC.cpp
+++ b/mlir/lib/Conversion/MemRefToEmitC/MemRefToEmitC.cpp
@@ -167,7 +167,9 @@ void mlir::populateMemRefToEmitCTypeConversion(TypeConverter &typeConverter) {
   typeConverter.addConversion(
       [&](MemRefType memRefType) -> std::optional<Type> {
         if (!memRefType.hasStaticShape() ||
-            !memRefType.getLayout().isIdentity() || memRefType.getRank() == 0) {
+            !memRefType.getLayout().isIdentity() || memRefType.getRank() == 0 ||
+            llvm::any_of(memRefType.getShape(),
+                         [](int64_t dim) { return dim == 0; })) {
           return {};
         }
         Type convertedElementType =
diff --git a/mlir/test/Conversion/MemRefToEmitC/memref-to-emitc-failed.mlir b/mlir/test/Conversion/MemRefToEmitC/memref-to-emitc-failed.mlir
index dee9cc97a14493..fda01974d3fc85 100644
--- a/mlir/test/Conversion/MemRefToEmitC/memref-to-emitc-failed.mlir
+++ b/mlir/test/Conversion/MemRefToEmitC/memref-to-emitc-failed.mlir
@@ -41,6 +41,22 @@ func.func @zero_rank() {
 
 // -----
 
+func.func @zero_dim_rank_1() {
+  // expected-error@+1 {{failed to legalize operation 'memref.alloca'}}
+  %0 = memref.alloca() : memref<0xf32>
+  return
+}
+
+// -----
+
+func.func @zero_dim_rank_3() {
+  // expected-error@+1 {{failed to legalize operation 'memref.alloca'}}
+  %0 = memref.alloca() : memref<2x0x4xf32>
+  return
+}
+
+// -----
+
 // expected-error@+1 {{failed to legalize operation 'memref.global'}}
 memref.global "nested" constant @nested_global : memref<3x7xf32>
 

[mgehre-amd]

Thanks!