Revert "[AlwaysInliner] Enable call site inlining to make flatten attribute working again (#53360)"

This reverts commit ceec438. Clang tests fail.

Author: davidbolvansky

clang/test/CodeGen/flatten.c

@@ -1,3 +1,9 @@
+// UNSUPPORTED: experimental-new-pass-manager
+// Currently, different code seems to be intentionally generated under the new
+// PM since we alwaysinline functions and not callsites under new PM.
+// Under new PM, f() will not be inlined from g() since f is not marked as
+// alwaysinline.
+
 // RUN: %clang_cc1 -triple=x86_64-linux-gnu %s -emit-llvm -o - | FileCheck %s
 
 void f(void) {}

clang/test/CodeGenCXX/flatten.cpp

@@ -1,3 +1,7 @@
+// UNSUPPORTED: experimental-new-pass-manager
+// See the comment for CodeGen/flatten.c on why this is unsupported with the new
+// PM.
+
 // RUN: %clang_cc1 -triple=x86_64-linux-gnu -std=c++11 %s -emit-llvm -o - | FileCheck %s
 
 void f(void) {}

llvm/lib/Transforms/IPO/AlwaysInliner.cpp

@@ -54,13 +54,13 @@ PreservedAnalyses AlwaysInlinerPass::run(Module &M,
     if (F.isPresplitCoroutine())
       continue;
 
-    if (!F.isDeclaration() && isInlineViable(F).isSuccess()) {
+    if (!F.isDeclaration() && F.hasFnAttribute(Attribute::AlwaysInline) &&
+        isInlineViable(F).isSuccess()) {
       Calls.clear();
 
       for (User *U : F.users())
         if (auto *CB = dyn_cast<CallBase>(U))
-          if (CB->getCalledFunction() == &F &&
-              CB->hasFnAttr(Attribute::AlwaysInline))
+          if (CB->getCalledFunction() == &F)
             Calls.insert(CB);
 
       for (CallBase *CB : Calls) {

llvm/test/Transforms/Coroutines/coro-retcon-once-private.ll

@@ -3,7 +3,9 @@
 target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-apple-macosx10.12.0"
 
-; CHECK-NOT: define {{.*}} @f(i8* %buffer, i32* %array)
+; CHECK: define internal { i8*, i32 } @f(i8* %buffer, i32* %array)
+; CHECK-NEXT: entry:
+; CHECK-NEXT:  unreachable
 
 define internal {i8*, i32} @f(i8* %buffer, i32* %array) {
 entry:

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

@@ -1,11 +1,14 @@
-; RUN: opt < %s -inline-threshold=0 -always-inline -enable-new-pm=0 -S | FileCheck %s --check-prefix=CHECK
+; RUN: opt < %s -inline-threshold=0 -always-inline -enable-new-pm=0 -S | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-CALL
 ;
 ; Ensure the threshold has no impact on these decisions.
-; RUN: opt < %s -inline-threshold=20000000 -always-inline -enable-new-pm=0 -S | FileCheck %s --check-prefix=CHECK
-; RUN: opt < %s -inline-threshold=-20000000 -always-inline -enable-new-pm=0 -S | FileCheck %s --check-prefix=CHECK
+; RUN: opt < %s -inline-threshold=20000000 -always-inline -enable-new-pm=0 -S | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-CALL
+; RUN: opt < %s -inline-threshold=-20000000 -always-inline -enable-new-pm=0 -S | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-CALL
 ;
 ; The new pass manager doesn't re-use any threshold based infrastructure for
-; the always inliner, but test that we get the correct result.
+; the always inliner, but test that we get the correct result. The new PM
+; always inliner also doesn't support inlining call-site alwaysinline
+; annotations. It isn't clear that this is a reasonable use case for
+; 'alwaysinline'.
 ; RUN: opt < %s -inline-threshold=0 -passes=always-inline -S | FileCheck %s --check-prefix=CHECK
 ; RUN: opt < %s -inline-threshold=20000000 -passes=always-inline -S | FileCheck %s --check-prefix=CHECK
 ; RUN: opt < %s -inline-threshold=-20000000 -passes=always-inline -S | FileCheck %s --check-prefix=CHECK
@@ -23,6 +26,12 @@ define i32 @outer1() {
    ret i32 %r
 }
 
+; The always inliner can't DCE arbitrary internal functions. PR2945
+define internal i32 @pr2945() nounwind {
+; CHECK-LABEL: @pr2945(
+  ret i32 0
+}
+
 define internal void @inner2(i32 %N) alwaysinline {
 ; CHECK-NOT: @inner2(
   %P = alloca i32, i32 %N
@@ -137,9 +146,10 @@ define i32 @inner7() {
   ret i32 1
 }
 define i32 @outer7() {
-; CHECK-LABEL: @outer7(
-; CHECK-NOT: call
-; CHECK: ret
+; CHECK-CALL-LABEL: @outer7(
+; CHECK-CALL-NOT: call
+; CHECK-CALL: ret
+
    %r = call i32 @inner7() alwaysinline
    ret i32 %r
 }