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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30271 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/README.txt b/lib/Target/X86/README.txt
index 394201c3c19fdff69241acff6006bf2f2090868d..110f399484bfe48b45455cf218b9a1384c5a699b 100644 (file)
--- a/lib/Target/X86/README.txt
+++ b/lib/Target/X86/README.txt
@@ -628,3 +628,17 @@ _test:
 
 This saves a movzbl, and saves a truncate if it doesn't get coallesced right.
 This is a simple DAGCombine to propagate the zext through the and.
+
+//===---------------------------------------------------------------------===//
+
+Instead of:
+
+       cmpl $4294967295, %edx
+       jg LBB1_8       #cond_false49
+
+emit:
+
+       testl %edx, %edx
+       js LBB1_8
+
+This saves a byte of code space.