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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@24572 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/README.txt b/lib/Target/X86/README.txt
index c9f23d598be5be31d889b4501ec6ebc422217f82..57aec86d2e5a7427589dd777da65d2d8f8052f0c 100644 (file)
--- a/lib/Target/X86/README.txt
+++ b/lib/Target/X86/README.txt
@@ -12,6 +12,12 @@ long long test(long long X, long long Y) { return X*Y; }
 by using the EAX result from the mul.  We should add a similar node for
 DIVREM.
 
+another case is:
+
+long long test(int X, int Y) { return (long long)X*Y; }
+
+... which should only be one imul instruction.
+
 //===---------------------------------------------------------------------===//
 
 This should be one DIV/IDIV instruction, not a libcall: