[mlir][spirv] Fix crash in spirv-lower-abi-attributes

... when the are no SPIR-V env attributes.

Fixes: #59983

Reviewed By: antiagainst

Differential Revision: https://reviews.llvm.org/D141695

Author: kuhar

mlir/lib/Dialect/SPIRV/Transforms/LowerABIAttributesPass.cpp

@@ -274,7 +274,12 @@ void LowerABIAttributesPass::runOnOperation() {
   spirv::ModuleOp module = getOperation();
   MLIRContext *context = &getContext();
 
-  spirv::TargetEnv targetEnv(spirv::lookupTargetEnv(module));
+  spirv::TargetEnvAttr targetEnvAttr = spirv::lookupTargetEnv(module);
+  if (!targetEnvAttr) {
+    module->emitOpError("missing SPIR-V target env attribute");
+    return signalPassFailure();
+  }
+  spirv::TargetEnv targetEnv(targetEnvAttr);
 
   SPIRVTypeConverter typeConverter(targetEnv);
 

mlir/test/Dialect/SPIRV/Transforms/abi-interface.mlir

@@ -1,4 +1,5 @@
-// RUN: mlir-opt -split-input-file -spirv-lower-abi-attrs %s | FileCheck %s
+// RUN: mlir-opt --split-input-file --spirv-lower-abi-attrs --verify-diagnostics %s \
+// RUN:   | FileCheck %s
 
 module attributes {
   spirv.target_env = #spirv.target_env<
@@ -31,3 +32,10 @@ spirv.module Logical GLSL450 {
 } // end spirv.module
 
 } // end module
+
+// -----
+
+module {
+// expected-error@+1 {{'spirv.module' op missing SPIR-V target env attribute}}
+spirv.module Logical GLSL450 {}
+} // end module