add some optimizations for strncpy/strncat and factor some
code. Patch by Benjamin Kramer!
llvm-svn: 68885
diff --git a/llvm/test/Transforms/SimplifyLibCalls/StrNCpy.ll b/llvm/test/Transforms/SimplifyLibCalls/StrNCpy.ll
new file mode 100644
index 0000000..011e9be
--- /dev/null
+++ b/llvm/test/Transforms/SimplifyLibCalls/StrNCpy.ll
@@ -0,0 +1,25 @@
+; Test that the StrNCpyOptimizer works correctly
+; RUN: llvm-as < %s | opt -simplify-libcalls | llvm-dis | \
+; RUN: not grep {call.*strncpy}
+
+@hello = constant [6 x i8] c"hello\00" ; <[6 x i8]*> [#uses=1]
+@null = constant [1 x i8] zeroinitializer ; <[1 x i8]*> [#uses=1]
+@null_hello = constant [7 x i8] c"\00hello\00" ; <[7 x i8]*> [#uses=1]
+
+declare i8* @strncpy(i8*, i8*, i32)
+
+declare i32 @puts(i8*)
+
+define i32 @main() {
+ %target = alloca [1024 x i8] ; <[1024 x i8]*> [#uses=1]
+ %arg1 = getelementptr [1024 x i8]* %target, i32 0, i32 0 ; <i8*> [#uses=2]
+ store i8 0, i8* %arg1
+ %arg2 = getelementptr [6 x i8]* @hello, i32 0, i32 0 ; <i8*> [#uses=1]
+ %rslt1 = call i8* @strncpy( i8* %arg1, i8* %arg2, i32 6 ) ; <i8*> [#uses=1]
+ %arg3 = getelementptr [1 x i8]* @null, i32 0, i32 0 ; <i8*> [#uses=1]
+ %rslt2 = call i8* @strncpy( i8* %rslt1, i8* %arg3, i32 42 ) ; <i8*> [#uses=1]
+ %arg4 = getelementptr [7 x i8]* @null_hello, i32 0, i32 0 ; <i8*> [#uses=1]
+ %rslt3 = call i8* @strncpy( i8* %rslt2, i8* %arg4, i32 42 ) ; <i8*> [#uses=1]
+ call i32 @puts( i8* %rslt3 ) ; <i32>:1 [#uses=0]
+ ret i32 0
+}