[AlwaysInliner] Check inliner errors even without assserts

When we build clang without asserts we should still check the result of
`InlineFunction()` to be sure there wasn't an error. Otherwise we could
incorrectly merge attributes in the next line.

This also removes a redundent call to `getCaller()`.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D121722

llvm/lib/Transforms/IPO/AlwaysInliner.cpp

@@ -75,18 +75,28 @@ PreservedAnalyses AlwaysInlinerPass::run(Module &M,
             },
             ORE);
         assert(OIC);
-        emitInlinedIntoBasedOnCost(ORE, CB->getDebugLoc(), CB->getParent(), F,
-                                   *Caller, *OIC, false, DEBUG_TYPE);
+        DebugLoc DLoc = CB->getDebugLoc();
+        BasicBlock *Block = CB->getParent();
+        emitInlinedIntoBasedOnCost(ORE, DLoc, Block, F, *Caller, *OIC, false,
+                                   DEBUG_TYPE);
 
         InlineFunctionInfo IFI(
             /*cg=*/nullptr, GetAssumptionCache, &PSI,
-            &FAM.getResult<BlockFrequencyAnalysis>(*(CB->getCaller())),
+            &FAM.getResult<BlockFrequencyAnalysis>(*Caller),
             &FAM.getResult<BlockFrequencyAnalysis>(F));
 
         InlineResult Res = InlineFunction(
             *CB, IFI, &FAM.getResult<AAManager>(F), InsertLifetime);
-        assert(Res.isSuccess() && "unexpected failure to inline");
-        (void)Res;
+        if (!Res.isSuccess()) {
+          ORE.emit([&]() {
+            return OptimizationRemarkMissed(DEBUG_TYPE, "NotInlined", DLoc,
+                                            Block)
+                   << "'" << ore::NV("Callee", &F) << "' is not inlined into '"
+                   << ore::NV("Caller", Caller)
+                   << "': " << ore::NV("Reason", Res.getFailureReason());
+          });
+          continue;
+        }
 
         // Merge the attributes based on the inlining.
         AttributeFuncs::mergeAttributesForInlining(*Caller, F);

llvm/test/Transforms/Inline/always-inline-remark.ll

@@ -0,0 +1,20 @@
+; RUN: opt -passes="always-inline" -pass-remarks-missed=inline -S < %s 2>&1 | FileCheck %s
+
+declare void @personalityFn1();
+declare void @personalityFn2();
+
+define void @foo() alwaysinline {
+    ret void
+}
+
+define void @bar() alwaysinline personality void ()* @personalityFn1 {
+    ret void
+}
+
+define void @goo() personality void ()* @personalityFn2 {
+    ; CHECK-DAG: 'bar' is not inlined into 'goo': incompatible personality
+    call void @bar()
+    ; CHECK-DAG: 'foo' is not inlined into 'goo': unsupported operand bundle
+    call void @foo() [ "CUSTOM_OPERAND_BUNDLE"() ]
+    ret void
+}