[CIR][CIRGen][NFC] Exceptions: Move the logic to create surrounding try to be close to call generation

Author: bcardosolopes

clang/lib/CIR/CodeGen/CIRGenCall.cpp

@@ -450,40 +450,69 @@ buildCallLikeOp(CIRGenFunction &CGF, mlir::Location callLoc,
                 mlir::cir::CallingConv callingConv,
                 mlir::cir::ExtraFuncAttributesAttr extraFnAttrs) {
   auto &builder = CGF.getBuilder();
+  auto getOrCreateSurroundingTryOp = [&]() {
+    // In OG, we build the landing pad for this scope. In CIR, we emit a
+    // synthetic cir.try because this didn't come from codegenerating from a
+    // try/catch in C++.
+    auto op = CGF.currLexScope->getClosestTryParent();
+    if (op)
+      return op;
+
+    op = builder.create<mlir::cir::TryOp>(
+        *CGF.currSrcLoc, /*scopeBuilder=*/
+        [&](mlir::OpBuilder &b, mlir::Location loc) {},
+        // Don't emit the code right away for catch clauses, for
+        // now create the regions and consume the try scope result.
+        // Note that clauses are later populated in
+        // CIRGenFunction::buildLandingPad.
+        [&](mlir::OpBuilder &b, mlir::Location loc,
+            mlir::OperationState &result) {
+          // Since this didn't come from an explicit try, we only need one
+          // handler: unwind.
+          auto *r = result.addRegion();
+          builder.createBlock(r);
+        });
+    op.setSynthetic(true);
+    return op;
+  };
 
   if (isInvoke) {
     // This call can throw, few options:
     //  - If this call does not have an associated cir.try, use the
     //    one provided by InvokeDest,
     //  - User written try/catch clauses require calls to handle
     //    exceptions under cir.try.
-    auto *invokeDest = CGF.getInvokeDest();
-    auto tryOp = dyn_cast_if_present<mlir::cir::TryOp>(invokeDest);
+    auto tryOp = getOrCreateSurroundingTryOp();
+    assert(tryOp && "expected");
+
     mlir::OpBuilder::InsertPoint ip = builder.saveInsertionPoint();
-    bool changeInsertion = tryOp && tryOp.getSynthetic();
-    if (changeInsertion) {
+    if (tryOp.getSynthetic()) {
       mlir::Block *lastBlock = &tryOp.getTryRegion().back();
       builder.setInsertionPointToStart(lastBlock);
     } else {
       assert(builder.getInsertionBlock() && "expected valid basic block");
     }
 
-    mlir::cir::CallOp tryCallOp;
+    mlir::cir::CallOp callOpWithExceptions;
     // TODO(cir): Set calling convention for `cir.try_call`.
     assert(callingConv == mlir::cir::CallingConv::C && "NYI");
     if (indirectFuncTy) {
-      tryCallOp = builder.createIndirectTryCallOp(callLoc, indirectFuncVal,
-                                                  indirectFuncTy, CIRCallArgs);
+      callOpWithExceptions = builder.createIndirectTryCallOp(
+          callLoc, indirectFuncVal, indirectFuncTy, CIRCallArgs);
     } else {
-      tryCallOp = builder.createTryCallOp(callLoc, directFuncOp, CIRCallArgs);
+      callOpWithExceptions =
+          builder.createTryCallOp(callLoc, directFuncOp, CIRCallArgs);
     }
-    tryCallOp->setAttr("extra_attrs", extraFnAttrs);
+    callOpWithExceptions->setAttr("extra_attrs", extraFnAttrs);
+
+    auto *invokeDest = CGF.getInvokeDest(tryOp);
+    (void)invokeDest;
 
-    if (changeInsertion) {
+    if (tryOp.getSynthetic()) {
       builder.create<mlir::cir::YieldOp>(tryOp.getLoc());
       builder.restoreInsertionPoint(ip);
     }
-    return tryCallOp;
+    return callOpWithExceptions;
   }
 
   assert(builder.getInsertionBlock() && "expected valid basic block");
@@ -731,7 +760,6 @@ RValue CIRGenFunction::buildCall(const CIRGenFunctionInfo &CallInfo,
               noThrowAttr.getMnemonic()))
         CannotThrow = true;
   }
-  // mlir::Operation *InvokeDest = CannotThrow ? nullptr : getInvokeDest();
   bool isInvoke = CannotThrow ? false : isInvokeDest();
 
   // TODO: UnusedReturnSizePtr

clang/lib/CIR/CodeGen/CIRGenCleanup.cpp

@@ -248,7 +248,7 @@ void CIRGenFunction::PopCleanupBlock(bool FallthroughIsBranchThrough) {
   if (!RequiresNormalCleanup) {
     // Mark CPP scope end for passed-by-value Arg temp
     //   per Windows ABI which is "normally" Cleanup in callee
-    if (IsEHa && getInvokeDest()) {
+    if (IsEHa && isInvokeDest()) {
       // If we are deactivating a normal cleanup then we don't have a
       // fallthrough. Restore original IP to emit CPP scope ends in the correct
       // block.
@@ -319,7 +319,7 @@ void CIRGenFunction::PopCleanupBlock(bool FallthroughIsBranchThrough) {
     if (!Personality.isMSVCPersonality()) {
       EHStack.pushTerminate();
       PushedTerminate = true;
-    } else if (IsEHa && getInvokeDest()) {
+    } else if (IsEHa && isInvokeDest()) {
       llvm_unreachable("NYI");
     }
 

clang/lib/CIR/CodeGen/CIRGenException.cpp

@@ -831,12 +831,10 @@ bool CIRGenFunction::isInvokeDest() {
   return true;
 }
 
-mlir::Operation *CIRGenFunction::getInvokeDestImpl() {
+mlir::Operation *CIRGenFunction::getInvokeDestImpl(mlir::cir::TryOp tryOp) {
   assert(EHStack.requiresLandingPad());
   assert(!EHStack.empty());
-
-  if (!isInvokeDest())
-    return nullptr;
+  assert(isInvokeDest());
 
   // Check the innermost scope for a cached landing pad.  If this is
   // a non-EH cleanup, we'll check enclosing scopes in EmitLandingPad.
@@ -850,43 +848,11 @@ mlir::Operation *CIRGenFunction::getInvokeDestImpl() {
   // if (!CurFn->hasPersonalityFn())
   //   CurFn->setPersonalityFn(getOpaquePersonalityFn(CGM, Personality));
 
-  auto createSurroundingTryOp = [&]() {
-    // In OG, we build the landing pad for this scope. In CIR, we emit a
-    // synthetic cir.try because this didn't come from codegenerating from a
-    // try/catch in C++.
-    auto tryOp = builder.create<mlir::cir::TryOp>(
-        *currSrcLoc, /*scopeBuilder=*/
-        [&](mlir::OpBuilder &b, mlir::Location loc) {},
-        // Don't emit the code right away for catch clauses, for
-        // now create the regions and consume the try scope result.
-        // Note that clauses are later populated in
-        // CIRGenFunction::buildLandingPad.
-        [&](mlir::OpBuilder &b, mlir::Location loc,
-            mlir::OperationState &result) {
-          // Since this didn't come from an explicit try, we only need one
-          // handler: unwind.
-          auto *r = result.addRegion();
-          builder.createBlock(r);
-        });
-    tryOp.setSynthetic(true);
-    return tryOp;
-  };
-
   if (Personality.usesFuncletPads()) {
     // We don't need separate landing pads in the funclet model.
     llvm::errs() << "PersonalityFn: " << Personality.PersonalityFn << "\n";
     llvm_unreachable("NYI");
   } else {
-    mlir::cir::TryOp tryOp = nullptr;
-    // Attempt to find a suitable existing parent try/catch, if none
-    // is available, create a synthetic cir.try in order to wrap the side
-    // effects of a potential throw.
-    if (currLexScope)
-      tryOp = currLexScope->getClosestTryParent();
-    if (!tryOp)
-      tryOp = createSurroundingTryOp();
-
-    assert(tryOp && "cir.try expected");
     LP = buildLandingPad(tryOp);
   }
 

clang/lib/CIR/CodeGen/CIRGenFunction.h

@@ -1759,13 +1759,13 @@ class CIRGenFunction : public CIRGenTypeCache {
   /// parameters.
   EHScopeStack::stable_iterator PrologueCleanupDepth;
 
-  mlir::Operation *getInvokeDestImpl();
-  mlir::Operation *getInvokeDest() {
+  mlir::Operation *getInvokeDestImpl(mlir::cir::TryOp tryOp);
+  mlir::Operation *getInvokeDest(mlir::cir::TryOp tryOp) {
     if (!EHStack.requiresLandingPad())
       return nullptr;
     // Return the respective cir.try, this can be used to compute
     // any other relevant information.
-    return getInvokeDestImpl();
+    return getInvokeDestImpl(tryOp);
   }
   bool isInvokeDest();
 

clang/lib/CIR/CodeGen/CIRGenItaniumCXXABI.cpp

@@ -2227,7 +2227,7 @@ void CIRGenItaniumCXXABI::buildThrow(CIRGenFunction &CGF,
 
   // FIXME: When adding support for invoking, we should wrap the throw op
   // below into a try, and let CFG flatten pass to generate a cir.try_call.
-  assert(!CGF.getInvokeDest() && "landing pad like logic NYI");
+  assert(!CGF.isInvokeDest() && "landing pad like logic NYI");
 
   // Now throw the exception.
   mlir::Location loc = CGF.getLoc(E->getSourceRange());