From: David Majnemer <david.majnemer@gmail.com>
Date: Thu, 25 Jun 2015 23:50:40 +0000 (+0000)
Subject: [CodeGen] Restrict isTriviallyRecursive to predefined lib functions forwarding to... 
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=f478e62b2cb8037d50e38deedfec39973ae88d0b;p=clang

[CodeGen] Restrict isTriviallyRecursive to predefined lib functions forwarding to lib functions

isTriviallyRecursive is only supposed to guard functions part of the
implementation.

This fixes PR23953.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@240735 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index bd7b44e413..d19d0ed886 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -1425,7 +1425,7 @@ namespace {
         return false;
       }
       unsigned BuiltinID = FD->getBuiltinID();
-      if (!BuiltinID)
+      if (!BuiltinID || !BI.isLibFunction(BuiltinID))
         return true;
       StringRef BuiltinName = BI.GetName(BuiltinID);
       if (BuiltinName.startswith("__builtin_") &&
@@ -1454,7 +1454,12 @@ CodeGenModule::isTriviallyRecursive(const FunctionDecl *FD) {
     Name = FD->getName();
   }
 
-  FunctionIsDirectlyRecursive Walker(Name, Context.BuiltinInfo);
+  auto &BI = Context.BuiltinInfo;
+  unsigned BuiltinID = Context.Idents.get(Name).getBuiltinID();
+  if (!BuiltinID || !BI.isPredefinedLibFunction(BuiltinID))
+    return false;
+
+  FunctionIsDirectlyRecursive Walker(Name, BI);
   Walker.TraverseFunctionDecl(const_cast<FunctionDecl*>(FD));
   return Walker.Result;
 }
diff --git a/test/CodeGen/pr9614.c b/test/CodeGen/pr9614.c
index 53abef1801..de21dbbb23 100644
--- a/test/CodeGen/pr9614.c
+++ b/test/CodeGen/pr9614.c
@@ -4,26 +4,35 @@ extern void foo_alias (void) __asm ("foo");
 inline void foo (void) {
   return foo_alias ();
 }
-extern void bar_alias (void) __asm ("bar");
-inline __attribute__ ((__always_inline__)) void bar (void) {
-  return bar_alias ();
+extern int abs_alias (int) __asm ("abs");
+inline __attribute__ ((__always_inline__)) int abs (int x) {
+  return abs_alias(x);
 }
 extern char *strrchr_foo (const char *__s, int __c)  __asm ("strrchr");
 extern inline __attribute__ ((__always_inline__)) __attribute__ ((__gnu_inline__)) char * strrchr_foo (const char *__s, int __c)  {
   return __builtin_strrchr (__s, __c);
 }
+
+extern inline void __attribute__((always_inline, __gnu_inline__))
+prefetch(void) {
+  __builtin_prefetch(0, 0, 1);
+}
+
 void f(void) {
   foo();
-  bar();
+  abs(0);
   strrchr_foo("", '.');
+  prefetch();
 }
 
 // CHECK-LABEL: define void @f()
 // CHECK: call void @foo()
-// CHECK-NEXT: call void @bar()
-// CHECK-NEXT: call i8* @strrchr(
-// CHECK-NEXT: ret void
+// CHECK: call i32 @abs(i32 0)
+// CHECK: call i8* @strrchr(
+// CHECK: call void @llvm.prefetch(
+// CHECK: ret void
 
 // CHECK: declare void @foo()
-// CHECK: declare void @bar()
+// CHECK: declare i32 @abs(i32
 // CHECK: declare i8* @strrchr(i8*, i32)
+// CHECK: declare void @llvm.prefetch(