Merge pull request #3498 from TNorthover/eng/PR-75451599

Coroutines: don't infer function attrs before lowering

Author: TNorthover

llvm/lib/Transforms/IPO/FunctionAttrs.cpp

@@ -1556,7 +1556,8 @@ static SCCNodesResult createSCCNodeSet(ArrayRef<Function *> Functions) {
   SCCNodesResult Res;
   Res.HasUnknownCall = false;
   for (Function *F : Functions) {
-    if (!F || F->hasOptNone() || F->hasFnAttribute(Attribute::Naked)) {
+    if (!F || F->hasOptNone() || F->hasFnAttribute(Attribute::Naked) ||
+        F->isPresplitCoroutine()) {
       // Treat any function we're trying not to optimize as if it were an
       // indirect call and omit it from the node set used below.
       Res.HasUnknownCall = true;

llvm/test/Transforms/Coroutines/coro-retcon-alloca.ll

@@ -10,7 +10,7 @@ define {i8*, i8*, i32} @f(i8* %buffer, i32 %n) {
 ; CHECK-NEXT:    [[N_VAL_SPILL_ADDR:%.*]] = getelementptr inbounds i8, i8* [[BUFFER:%.*]], i64 8
 ; CHECK-NEXT:    [[TMP0:%.*]] = bitcast i8* [[N_VAL_SPILL_ADDR]] to i32*
 ; CHECK-NEXT:    store i32 [[N:%.*]], i32* [[TMP0]], align 4
-; CHECK-NEXT:    [[TMP1:%.*]] = tail call i8* @allocate(i32 [[N]]) #[[ATTR0:[0-9]+]]
+; CHECK-NEXT:    [[TMP1:%.*]] = tail call i8* @allocate(i32 [[N]])
 ; CHECK-NEXT:    [[DOTSPILL_ADDR:%.*]] = bitcast i8* [[BUFFER]] to i8**
 ; CHECK-NEXT:    store i8* [[TMP1]], i8** [[DOTSPILL_ADDR]], align 8
 ; CHECK-NEXT:    [[TMP2:%.*]] = insertvalue { i8*, i8*, i32 } { i8* bitcast ({ i8*, i8*, i32 } (i8*, i1)* @f.resume.0 to i8*), i8* undef, i32 undef }, i8* [[TMP1]], 1

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

@@ -72,7 +72,7 @@ entry:
 define hidden { i8*, i8* } @g(i8* %buffer, i16* %ptr) {
 ; CHECK-LABEL: @g(
 ; CHECK-NEXT:  coro.return:
-; CHECK-NEXT:    [[TMP0:%.*]] = tail call i8* @allocate(i32 8) #[[ATTR0:[0-9]+]]
+; CHECK-NEXT:    [[TMP0:%.*]] = tail call i8* @allocate(i32 8)
 ; CHECK-NEXT:    [[TMP1:%.*]] = bitcast i8* [[BUFFER:%.*]] to i8**
 ; CHECK-NEXT:    store i8* [[TMP0]], i8** [[TMP1]], align 8
 ; CHECK-NEXT:    [[PTR_SPILL_ADDR:%.*]] = bitcast i8* [[TMP0]] to i16**

llvm/test/Transforms/FunctionAttrs/noreturn.ll

@@ -71,3 +71,20 @@ define void @callsite_noreturn() {
   call i32 @f() noreturn
   ret void
 }
+
+; CHECK: Function Attrs: {{.*}}noreturn
+; CHECK-NEXT: @unreachable
+define void @unreachable() {
+  unreachable
+}
+
+; CHECK-NOT: Function Attrs: {{.*}}noreturn
+; CHECK: @coro
+define void @coro() "coroutine.presplit"="1" {
+  call token @llvm.coro.id.retcon.once(i32 0, i32 0, i8* null, i8* bitcast(void() *@coro to i8*), i8* null, i8* null)
+  call i1 @llvm.coro.end(i8* null, i1 false)
+  unreachable
+}
+
+declare token @llvm.coro.id.retcon.once(i32 %size, i32 %align, i8* %buffer, i8* %prototype, i8* %alloc, i8* %free)
+declare i1 @llvm.coro.end(i8*, i1)