[llvm-commits] [llvm] r47830 - /llvm/trunk/lib/Target/PowerPC/README.txt

[Chris Lattner]

Author: lattner
Date: Sun Mar  2 13:27:34 2008
New Revision: 47830

URL: http://llvm.org/viewvc/llvm-project?rev=47830&view=rev
Log:
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Modified:
    llvm/trunk/lib/Target/PowerPC/README.txt

Modified: llvm/trunk/lib/Target/PowerPC/README.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/PowerPC/README.txt?rev=47830&r1=47829&r2=47830&view=diff

==============================================================================
--- llvm/trunk/lib/Target/PowerPC/README.txt (original)
+++ llvm/trunk/lib/Target/PowerPC/README.txt Sun Mar  2 13:27:34 2008
@@ -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.
+
+//===---------------------------------------------------------------------===//