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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126719 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/README.txt b/lib/Target/README.txt
index e01df0104367295a651f35869c303e92173841e6..45da3ddb607a1532a3b24faeed0549895271b308 100644 (file)
--- a/lib/Target/README.txt
+++ b/lib/Target/README.txt
@@ -1325,6 +1325,21 @@ codegen.
 
 //===---------------------------------------------------------------------===//
 
+simplifylibcalls should turn these snprintf idioms into memcpy (GCC PR47917)
+
+char buf1[6], buf2[6], buf3[4], buf4[4];
+int i;
+
+int foo (void) {
+  int ret = snprintf (buf1, sizeof buf1, "abcde");
+  ret += snprintf (buf2, sizeof buf2, "abcdef") * 16;
+  ret += snprintf (buf3, sizeof buf3, "%s", i++ < 6 ? "abc" : "def") * 256;
+  ret += snprintf (buf4, sizeof buf4, "%s", i++ > 10 ? "abcde" : "defgh")*4096;
+  return ret;
+}
+
+//===---------------------------------------------------------------------===//
+
 "gas" uses this idiom:
   else if (strchr ("+-/*%|&^:[]()~", *intel_parser.op_string))
 ..