Emit an error message if the value passed to __builtin_returnaddress isn't a constant

__builtin_returnaddress requires that the value passed into is be a constant.
However, at -O0 even a constant expression may not be converted to a constant.
Emit an error message intead of crashing.

llvm-svn: 198531

1 files changed, 27 insertions, 0 deletions

diff --git a/llvm/test/CodeGen/Generic/builtin-returnaddress-error.ll b/llvm/test/CodeGen/Generic/builtin-returnaddress-error.ll
new file mode 100644
index 00000000000..d3bd1571523
--- /dev/null
+++ b/llvm/test/CodeGen/Generic/builtin-returnaddress-error.ll
@@ -0,0 +1,27 @@
+; RUN: not llc < %s -O0 2> %t1
+; RUN: FileCheck %s < %t1
+
+; CHECK: argument to '__builtin_return_address' must be a constant integer
+
+define i32* @foo() {
+entry:
+  %t1 = call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 0, i32 0)
+  %t2 = extractvalue { i32, i1 } %t1, 0
+  %t3 = extractvalue { i32, i1 } %t1, 1
+  br i1 %t3, label %cont, label %trap
+
+trap:
+  call void @llvm.trap()
+  unreachable
+
+cont:
+  %t5 = call i8* @llvm.returnaddress(i32 %t2)
+  %t6 = bitcast i8* %t5 to i32*
+  ret i32* %t6
+}
+
+declare { i32, i1 } @llvm.sadd.with.overflow.i32(i32, i32)
+
+declare void @llvm.trap()
+
+declare i8* @llvm.returnaddress(i32)