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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30581 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/ARM/README.txt b/lib/Target/ARM/README.txt
index 7d612d019b95969ade5684fb82a7a84ab045558a..736d776fd876b1e7bae053d317ff722ce0878650 100644 (file)
--- a/lib/Target/ARM/README.txt
+++ b/lib/Target/ARM/README.txt
@@ -7,3 +7,24 @@ Consider implementing a select with two conditional moves:
 cmp x, y
 moveq dst, a
 movne dst, b
+
+----------------------------------------------------------
+
+
+%tmp1 = shl int %b, ubyte %c
+%tmp4 = add int %a, %tmp1
+
+compiles to
+
+add r0, r0, r1, lsl r2
+
+but
+
+%tmp1 = shl int %b, ubyte %c
+%tmp4 = add int %tmp1, %a
+
+compiles to
+mov r1, r1, lsl r2
+add r0, r1, r0
+
+----------------------------------------------------------