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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35530 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/PowerPC/README.txt b/lib/Target/PowerPC/README.txt
index 864302f687f42477d6cc3b91319d0f99dc15a894..69e60fcb92230ba0ba31894ee503d12b4d08d20a 100644 (file)
--- a/lib/Target/PowerPC/README.txt
+++ b/lib/Target/PowerPC/README.txt
@@ -639,3 +639,26 @@ __ZNK4llvm5APInt17countLeadingZerosEv:
 The dead or is a 'truncate' from 64- to 32-bits.
 
 ===-------------------------------------------------------------------------===
+
+We generate horrible ppc code for this:
+
+#define N  2000000
+double   a[N],c[N];
+void simpleloop() {
+   int j;
+   for (j=0; j<N; j++)
+     c[j] = a[j];
+}
+
+LBB1_1: ;bb
+        lfdx f0, r3, r4
+        addi r5, r5, 1                 ;; Extra IV for the exit value compare.
+        stfdx f0, r2, r4
+        addi r4, r4, 8
+
+        xoris r6, r5, 30               ;; This is due to a large immediate.
+        cmplwi cr0, r6, 33920
+        bne cr0, LBB1_1
+
+===-------------------------------------------------------------------------===
+