[Attributor] Shortcut no-return through will-return

No-return and will-return are exclusive, assuming the latter is more
prominent we can avoid updates of the former unless will-return is not
known for sure.

llvm-svn: 374739

6 files changed, 18 insertions, 6 deletions

diff --git a/llvm/test/Transforms/FunctionAttrs/fn_noreturn.ll b/llvm/test/Transforms/FunctionAttrs/fn_noreturn.ll
index e3a0f0b2504..b9139c5571a 100644
--- a/llvm/test/Transforms/FunctionAttrs/fn_noreturn.ll
+++ b/llvm/test/Transforms/FunctionAttrs/fn_noreturn.ll
@@ -1,4 +1,4 @@
-; RUN: opt -functionattrs -attributor -attributor-disable=false -attributor-max-iterations-verify -attributor-max-iterations=2 -S < %s | FileCheck %s
+; RUN: opt -functionattrs -attributor -attributor-disable=false -attributor-max-iterations-verify -attributor-max-iterations=3 -S < %s | FileCheck %s
 ;
 ; Test cases specifically designed for the "no-return" function attribute.
 ; We use FIXME's to indicate problems and missing attributes.
@@ -124,4 +124,16 @@ cond.end:                                         ; preds = %cond.false, %cond.t
   ret i32 %cond
 }
 
+
+; TEST 6: willreturn means *not* no-return
+; CHECK:      Function Attrs: nofree norecurse nosync nounwind readnone willreturn
+; CHECK-NEXT: define i32 @endless_loop_but_willreturn
+define i32 @endless_loop_but_willreturn(i32 %a) willreturn {
+entry:
+  br label %while.body
+
+while.body:                                       ; preds = %entry, %while.body
+  br label %while.body
+}
+
 attributes #0 = { noinline nounwind uwtable }
diff --git a/llvm/test/Transforms/FunctionAttrs/internal-noalias.ll b/llvm/test/Transforms/FunctionAttrs/internal-noalias.ll
index 9c4158acebf..30667ef13f6 100644
--- a/llvm/test/Transforms/FunctionAttrs/internal-noalias.ll
+++ b/llvm/test/Transforms/FunctionAttrs/internal-noalias.ll
@@ -1,4 +1,4 @@
-; RUN: opt -S -passes=attributor -aa-pipeline='basic-aa' -attributor-disable=false -attributor-max-iterations-verify -attributor-max-iterations=5 < %s | FileCheck %s
+; RUN: opt -S -passes=attributor -aa-pipeline='basic-aa' -attributor-disable=false -attributor-max-iterations-verify -attributor-max-iterations=3 < %s | FileCheck %s
 
 define dso_local i32 @visible(i32* noalias %A, i32* noalias %B) #0 {
 entry:
diff --git a/llvm/test/Transforms/FunctionAttrs/liveness.ll b/llvm/test/Transforms/FunctionAttrs/liveness.ll
index b6a4900d2af..e1bcb31d288 100644
--- a/llvm/test/Transforms/FunctionAttrs/liveness.ll
+++ b/llvm/test/Transforms/FunctionAttrs/liveness.ll
@@ -1,4 +1,4 @@
-; RUN: opt -attributor --attributor-disable=false -attributor-max-iterations-verify -attributor-max-iterations=2 -S < %s | FileCheck %s
+; RUN: opt -attributor --attributor-disable=false -attributor-max-iterations-verify -attributor-max-iterations=3 -S < %s | FileCheck %s
 
 declare void @no_return_call() nofree noreturn nounwind readnone
 
diff --git a/llvm/test/Transforms/FunctionAttrs/norecurse.ll b/llvm/test/Transforms/FunctionAttrs/norecurse.ll
index 1b22d4858e0..6a4d1180231 100644
--- a/llvm/test/Transforms/FunctionAttrs/norecurse.ll
+++ b/llvm/test/Transforms/FunctionAttrs/norecurse.ll
@@ -1,6 +1,6 @@
 ; RUN: opt < %s -basicaa -functionattrs -rpo-functionattrs -S | FileCheck %s --check-prefixes=CHECK,BOTH
 ; RUN: opt < %s -aa-pipeline=basic-aa -passes='cgscc(function-attrs),rpo-functionattrs' -S | FileCheck %s --check-prefixes=CHECK,BOTH
-; RUN: opt -passes=attributor --attributor-disable=false -attributor-max-iterations-verify -attributor-max-iterations=2 -S < %s | FileCheck %s --check-prefixes=ATTRIBUTOR,BOTH
+; RUN: opt -passes=attributor --attributor-disable=false -attributor-max-iterations-verify -attributor-max-iterations=4 -S < %s | FileCheck %s --check-prefixes=ATTRIBUTOR,BOTH
 
 ; CHECK: Function Attrs
 ; CHECK-SAME: norecurse nounwind readnone
diff --git a/llvm/test/Transforms/FunctionAttrs/noreturn_async.ll b/llvm/test/Transforms/FunctionAttrs/noreturn_async.ll
index e06a13f40c5..b7e9b0f4058 100644
--- a/llvm/test/Transforms/FunctionAttrs/noreturn_async.ll
+++ b/llvm/test/Transforms/FunctionAttrs/noreturn_async.ll
@@ -1,4 +1,4 @@
-; RUN: opt -functionattrs -attributor -attributor-disable=false -attributor-max-iterations-verify -attributor-max-iterations=2 -S < %s | FileCheck %s
+; RUN: opt -functionattrs -attributor -attributor-disable=false -attributor-max-iterations-verify -attributor-max-iterations=3 -S < %s | FileCheck %s
 ;
 ; This file is the same as noreturn_sync.ll but with a personality which
 ; indicates that the exception handler *can* catch asynchronous exceptions. As
diff --git a/llvm/test/Transforms/FunctionAttrs/noreturn_sync.ll b/llvm/test/Transforms/FunctionAttrs/noreturn_sync.ll
index 423a369f704..8e583cf9bc4 100644
--- a/llvm/test/Transforms/FunctionAttrs/noreturn_sync.ll
+++ b/llvm/test/Transforms/FunctionAttrs/noreturn_sync.ll
@@ -1,4 +1,4 @@
-; RUN: opt -functionattrs -attributor -attributor-disable=false -attributor-max-iterations-verify -attributor-max-iterations=2 -S < %s | FileCheck %s
+; RUN: opt -functionattrs -attributor -attributor-disable=false -attributor-max-iterations-verify -attributor-max-iterations=3 -S < %s | FileCheck %s
 ;
 ; This file is the same as noreturn_async.ll but with a personality which
 ; indicates that the exception handler *cannot* catch asynchronous exceptions.