Add a note about a cute little fabs optimization.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153543 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/README.txt b/lib/Target/README.txt
index 2d4925d307a5aee5cc6057519711d748193b8e03..8929ac4f2a610aad46fb37dc83bbc90f6c5f2996 100644 (file)
--- a/lib/Target/README.txt
+++ b/lib/Target/README.txt
@@ -2370,3 +2370,8 @@ unsigned foo(unsigned x, unsigned y) { return x > y && x != 0; }
 should fold to x > y.
 
 //===---------------------------------------------------------------------===//
+
+int f(double x) { return __builtin_fabs(x) < 0.0; }
+should fold to false.
+
+//===---------------------------------------------------------------------===//