<div dir="ltr">My bad !! Yes, its -instsimplify<br><br><br></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Fri, Jun 27, 2014 at 11:21 PM, Nick Lewycky <span dir="ltr"><<a href="mailto:nlewycky@google.com" target="_blank">nlewycky@google.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div class="gmail_extra"><div class="gmail_quote"><div class="">On 27 June 2014 05:31, suyog <span dir="ltr"><<a href="mailto:suyog.sarda@samsung.com" target="_blank">suyog.sarda@samsung.com</a>></span> wrote:<br>
</div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">

Hi Nick,<br>
<br>
I modified the test case to use FileCheck.<br>
<br>
I also believe the test case is in accordance to what we taught instsimplify as mentioned by Rahul above.<br>
Also, this test case was the original one for instcombine, the code for which we moved to instsimplify.<br>
<br>
Can you point out what's specific wrong in the test case? Your inputs are most welcomed :)<div class=""><br>
<div><br>
<a href="http://reviews.llvm.org/D4102" target="_blank">http://reviews.llvm.org/D4102</a><br>
<br>
Files:<br>
  lib/Analysis/InstructionSimplify.cpp<br>
  lib/Transforms/InstCombine/InstCombineShifts.cpp<br>
</div></div>  test/Transforms/InstSimplify/ashr-nop.ll<div class=""><br>
<div><br>
Index: lib/Analysis/InstructionSimplify.cpp<br>
===================================================================<br>
--- lib/Analysis/InstructionSimplify.cpp<br>
+++ lib/Analysis/InstructionSimplify.cpp<br>
</div></div>@@ -1346,6 +1346,11 @@<div class=""><br>
<div>       cast<OverflowingBinaryOperator>(Op0)->hasNoSignedWrap())<br>
     return X;<br>
<br>
+  // Arithmetic shifting an all-sign-bit value is a no-op.<br>
+  unsigned NumSignBits = ComputeNumSignBits(Op0);<br>
+  if (NumSignBits == Op0->getType()->getScalarSizeInBits())<br>
+    return Op0;<br>
+<br>
   return nullptr;<br>
 }<br>
<br>
Index: lib/Transforms/InstCombine/InstCombineShifts.cpp<br>
===================================================================<br>
--- lib/Transforms/InstCombine/InstCombineShifts.cpp<br>
+++ lib/Transforms/InstCombine/InstCombineShifts.cpp<br>
</div></div>@@ -815,10 +815,5 @@<div class=""><br>
<div>                         APInt::getSignBit(I.getType()->getScalarSizeInBits())))<br>
     return BinaryOperator::CreateLShr(Op0, Op1);<br>
<br>
-  // Arithmetic shifting an all-sign-bit value is a no-op.<br>
-  unsigned NumSignBits = ComputeNumSignBits(Op0);<br>
-  if (NumSignBits == Op0->getType()->getScalarSizeInBits())<br>
-    return ReplaceInstUsesWith(I, Op0);<br>
-<br>
   return nullptr;<br>
 }<br>
</div></div><div class=""><div>Index: test/Transforms/InstSimplify/ashr-nop.ll<br>
===================================================================<br>
--- test/Transforms/InstSimplify/ashr-nop.ll<br>
+++ test/Transforms/InstSimplify/ashr-nop.ll<br>
</div></div>@@ -0,0 +1,10 @@<br>
+; RUN: opt < %s -instcombine -S | FileCheck %s<br></blockquote><div><br></div><div>Did you mean -instsimplify?</div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">



+<br>
+; CHECK-LABEL: @foo<br>
+; CHECK-NOT: ashr<div class=""><br>
<div><div>+define i32 @foo(i32 %x) {<br>
+  %o = and i32 %x, 1<br>
+  %n = add i32 %o, -1<br>
+  %t = ashr i32 %n, 17<br>
+  ret i32 %t<br>
+}<br>
</div></div></div></blockquote></div><br></div></div>
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<br></blockquote></div><br><br clear="all"><br>-- <br>With regards,<br>Suyog Sarda<br>
</div>