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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26523 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 17 insertions, 0 deletions

diff --git a/lib/Target/README.txt b/lib/Target/README.txt
index 2ce2575d1c..cdadb26806 100644
--- a/lib/Target/README.txt
+++ b/lib/Target/README.txt
@@ -101,3 +101,20 @@ into:
 
 This would be a win on ppc32, but not x86 or ppc64.
 
+//===---------------------------------------------------------------------===//
+
+Pull add through mul/shift to handle this:
+
+int foo(int P[4][4], int i) {
+  return P[i+2][1];
+}
+
+better than this (no addi needed):
+
+_foo:
+        addi r2, r4, 2
+        slwi r2, r2, 4
+        add r2, r3, r2
+        lwz r3, 4(r2)
+        blr
+