Changes in directory llvm/lib/Target:
README.txt updated: 1.33 -> 1.34
---
Log message:
Add a note
---
Diffs of the changes: (+19 -0)
README.txt | 19 +++++++++++++++++++
1 files changed, 19 insertions(+)
Index: llvm/lib/Target/README.txt
diff -u llvm/lib/Target/README.txt:1.33 llvm/lib/Target/README.txt:1.34
--- llvm/lib/Target/README.txt:1.33 Sat May 20 22:57:07 2006
+++ llvm/lib/Target/README.txt Tue May 30 16:29:15 2006
@@ -251,3 +251,22 @@
ret void
}
+//===---------------------------------------------------------------------===//
+
+dag/inst combine "clz(x)>>5 -> x==0" for 32-bit x.
+
+Compile:
+
+int bar(int x)
+{
+ int t = __builtin_clz(x);
+ return -(t>>5);
+}
+
+to:
+
+_bar: addic r3,r3,-1
+ subfe r3,r3,r3
+ blr
+
+
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