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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47830 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/README.txt b/lib/Target/PowerPC/README.txt
index 7bc50e5..55baf8d 100644
--- a/lib/Target/PowerPC/README.txt
+++ b/lib/Target/PowerPC/README.txt
@@ -714,3 +714,42 @@
which is more efficient and can use mfocr. See PR642 for some more context.
//===---------------------------------------------------------------------===//
+
+void foo(float *data, float d) {
+ long i;
+ for (i = 0; i < 8000; i++)
+ data[i] = d;
+}
+void foo2(float *data, float d) {
+ long i;
+ data--;
+ for (i = 0; i < 8000; i++) {
+ data[1] = d;
+ data++;
+ }
+}
+
+These compile to:
+
+_foo:
+ li r2, 0
+LBB1_1: ; bb
+ addi r4, r2, 4
+ stfsx f1, r3, r2
+ cmplwi cr0, r4, 32000
+ mr r2, r4
+ bne cr0, LBB1_1 ; bb
+ blr
+_foo2:
+ li r2, 0
+LBB2_1: ; bb
+ addi r4, r2, 4
+ stfsx f1, r3, r2
+ cmplwi cr0, r4, 32000
+ mr r2, r4
+ bne cr0, LBB2_1 ; bb
+ blr
+
+The 'mr' could be eliminated to folding the add into the cmp better.
+
+//===---------------------------------------------------------------------===//