From: Mike Pall <mike>
Date: Sun, 7 Oct 2012 15:12:28 +0000 (+0200)
Subject: PPC: Fix string.sub() range check.
X-Git-Tag: v2.0.0-beta11~24
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c681e009c0c5cba5622b863b914c19cfbf6cc147;p=thirdparty%2FLuaJIT.git

PPC: Fix string.sub() range check.
---

diff --git a/src/vm_ppc.dasc b/src/vm_ppc.dasc
index 7eafebe1..5a6737ae 100644
--- a/src/vm_ppc.dasc
+++ b/src/vm_ppc.dasc
@@ -2100,10 +2100,10 @@ static void build_subroutines(BuildCtx *ctx)
   |  b ->fff_newstr
   |
   |5:  // Negative end or overflow.
-  |  sub CARG2, TMP0, TMP2
-  |  srawi CARG2, CARG2, 31
-  |  andc TMP3, TMP3, CARG2		// end = end > len ? len : end+len+1
-  |  add TMP2, TMP0, TMP3
+  |  cmpw TMP0, TMP2			// len >= end? (signed compare)
+  |   add TMP2, TMP0, TMP3		// Negative end: end = end+len+1.
+  |  bge <2
+  |   mr TMP2, TMP0			// Overflow: end = len.
   |  b <2
   |
   |7:  // Negative start or underflow.