[clang-tidy][mlir] Make rewrite more conservative.

[jpienaar]

Don't create a fix where object invoked on is a temporary object as create method requires a reference.

[llvmbot]

@llvm/pr-subscribers-clang-tidy

Author: Jacques Pienaar (jpienaar)

Changes

Don't create a fix where object invoked on is a temporary object as create method requires a reference.

---

Full diff: https://github.com/llvm/llvm-project/pull/150757.diff

2 Files Affected:

• (modified) clang-tools-extra/clang-tidy/llvm/UseNewMLIROpBuilderCheck.cpp (+12-5)
• (modified) clang-tools-extra/test/clang-tidy/checkers/llvm/use-new-mlir-op-builder.cpp (+3)

diff --git a/clang-tools-extra/clang-tidy/llvm/UseNewMLIROpBuilderCheck.cpp b/clang-tools-extra/clang-tidy/llvm/UseNewMLIROpBuilderCheck.cpp
index 0b28ea2508977..131c5c32eb780 100644
--- a/clang-tools-extra/clang-tidy/llvm/UseNewMLIROpBuilderCheck.cpp
+++ b/clang-tools-extra/clang-tidy/llvm/UseNewMLIROpBuilderCheck.cpp
@@ -111,17 +111,24 @@ EditGenerator rewrite(RangeSelector Call, RangeSelector Builder,
 }
 
 RewriteRuleWith<std::string> useNewMlirOpBuilderCheckRule() {
-  return makeRule(
+  Stencil message = cat("use 'OpType::create(builder, ...)' instead of "
+                        "'builder.create<OpType>(...)'");
+  // Match a create call on an OpBuilder.
+  ast_matchers::internal::Matcher<Stmt> base =
       cxxMemberCallExpr(
           on(expr(hasType(
                       cxxRecordDecl(isSameOrDerivedFrom("::mlir::OpBuilder"))))
                  .bind("builder")),
           callee(cxxMethodDecl(hasTemplateArgument(0, templateArgument()))),
           callee(cxxMethodDecl(hasName("create"))))
-          .bind("call"),
-      rewrite(node("call"), node("builder"), callArgs("call")),
-      cat("use 'OpType::create(builder, ...)' instead of "
-          "'builder.create<OpType>(...)'"));
+          .bind("call");
+  return applyFirst(
+      {// Attempt to rewrite with a concrete builder.
+       makeRule(cxxMemberCallExpr(unless(on(cxxTemporaryObjectExpr())), base),
+                rewrite(node("call"), node("builder"), callArgs("call")),
+                message),
+       // Warn on calls on temporary objects only.
+       makeRule(base, noopEdit(node("call")), message)});
 }
 } // namespace
 
diff --git a/clang-tools-extra/test/clang-tidy/checkers/llvm/use-new-mlir-op-builder.cpp b/clang-tools-extra/test/clang-tidy/checkers/llvm/use-new-mlir-op-builder.cpp
index 57e026c10bf53..3b8d5da968f7f 100644
--- a/clang-tools-extra/test/clang-tidy/checkers/llvm/use-new-mlir-op-builder.cpp
+++ b/clang-tools-extra/test/clang-tidy/checkers/llvm/use-new-mlir-op-builder.cpp
@@ -69,4 +69,7 @@ void f() {
   // CHECK-MESSAGES: :[[@LINE+2]]:3: warning: use 'OpType::create(builder, ...)' instead of 'builder.create<OpType>(...)' [llvm-use-new-mlir-op-builder]
   // CHECK-FIXES: mlir::ModuleOp::create(ib)
   ib.create<mlir::ModuleOp>(   );
+
+  // CHECK-MESSAGES: :[[@LINE+1]]:3: warning: use 'OpType::create(builder, ...)' instead of 'builder.create<OpType>(...)' [llvm-use-new-mlir-op-builder]
+  mlir::OpBuilder().create<mlir::ModuleOp>(builder.getUnknownLoc());
 }

[llvmbot]

@llvm/pr-subscribers-clang-tools-extra

Author: Jacques Pienaar (jpienaar)

Changes

Don't create a fix where object invoked on is a temporary object as create method requires a reference.

---

Full diff: https://github.com/llvm/llvm-project/pull/150757.diff

2 Files Affected:

• (modified) clang-tools-extra/clang-tidy/llvm/UseNewMLIROpBuilderCheck.cpp (+12-5)
• (modified) clang-tools-extra/test/clang-tidy/checkers/llvm/use-new-mlir-op-builder.cpp (+3)

diff --git a/clang-tools-extra/clang-tidy/llvm/UseNewMLIROpBuilderCheck.cpp b/clang-tools-extra/clang-tidy/llvm/UseNewMLIROpBuilderCheck.cpp
index 0b28ea2508977..131c5c32eb780 100644
--- a/clang-tools-extra/clang-tidy/llvm/UseNewMLIROpBuilderCheck.cpp
+++ b/clang-tools-extra/clang-tidy/llvm/UseNewMLIROpBuilderCheck.cpp
@@ -111,17 +111,24 @@ EditGenerator rewrite(RangeSelector Call, RangeSelector Builder,
 }
 
 RewriteRuleWith<std::string> useNewMlirOpBuilderCheckRule() {
-  return makeRule(
+  Stencil message = cat("use 'OpType::create(builder, ...)' instead of "
+                        "'builder.create<OpType>(...)'");
+  // Match a create call on an OpBuilder.
+  ast_matchers::internal::Matcher<Stmt> base =
       cxxMemberCallExpr(
           on(expr(hasType(
                       cxxRecordDecl(isSameOrDerivedFrom("::mlir::OpBuilder"))))
                  .bind("builder")),
           callee(cxxMethodDecl(hasTemplateArgument(0, templateArgument()))),
           callee(cxxMethodDecl(hasName("create"))))
-          .bind("call"),
-      rewrite(node("call"), node("builder"), callArgs("call")),
-      cat("use 'OpType::create(builder, ...)' instead of "
-          "'builder.create<OpType>(...)'"));
+          .bind("call");
+  return applyFirst(
+      {// Attempt to rewrite with a concrete builder.
+       makeRule(cxxMemberCallExpr(unless(on(cxxTemporaryObjectExpr())), base),
+                rewrite(node("call"), node("builder"), callArgs("call")),
+                message),
+       // Warn on calls on temporary objects only.
+       makeRule(base, noopEdit(node("call")), message)});
 }
 } // namespace
 
diff --git a/clang-tools-extra/test/clang-tidy/checkers/llvm/use-new-mlir-op-builder.cpp b/clang-tools-extra/test/clang-tidy/checkers/llvm/use-new-mlir-op-builder.cpp
index 57e026c10bf53..3b8d5da968f7f 100644
--- a/clang-tools-extra/test/clang-tidy/checkers/llvm/use-new-mlir-op-builder.cpp
+++ b/clang-tools-extra/test/clang-tidy/checkers/llvm/use-new-mlir-op-builder.cpp
@@ -69,4 +69,7 @@ void f() {
   // CHECK-MESSAGES: :[[@LINE+2]]:3: warning: use 'OpType::create(builder, ...)' instead of 'builder.create<OpType>(...)' [llvm-use-new-mlir-op-builder]
   // CHECK-FIXES: mlir::ModuleOp::create(ib)
   ib.create<mlir::ModuleOp>(   );
+
+  // CHECK-MESSAGES: :[[@LINE+1]]:3: warning: use 'OpType::create(builder, ...)' instead of 'builder.create<OpType>(...)' [llvm-use-new-mlir-op-builder]
+  mlir::OpBuilder().create<mlir::ModuleOp>(builder.getUnknownLoc());
 }

[joker-eph]

I'm confused about the comment here.
Isn't this "always warn, but rewrite only when having a lvalue builder"?

[jpienaar]

Yes this is meant as "Warn only" on temporary as in, don't attempt rewrite. I can perhaps combine both comments to one as you wrote.

[jpienaar]

I'm going to wait a little bit longer to see if anyone has any further comment (I think this is relatively direct one, but wanted to make sure).

[vbvictor]

LGTM with nit

[HerrCai0907]

lgtm