[llvm-commits] [llvm] r142992 - in /llvm/trunk: lib/VMCore/Instructions.cpp test/Bitcode/shuffle.ll

[Mon P Wang]

Author: wangmp
Date: Tue Oct 25 19:34:48 2011
New Revision: 142992

URL: http://llvm.org/viewvc/llvm-project?rev=142992&view=rev
Log:
The bitcode reader can create an shuffle with a place holder mask which it will
fix up later. For this special case, allow such a mask to be considered valid.
<rdar://problem/8622574>

Added:
    llvm/trunk/test/Bitcode/shuffle.ll
Modified:
    llvm/trunk/lib/VMCore/Instructions.cpp

Modified: llvm/trunk/lib/VMCore/Instructions.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/VMCore/Instructions.cpp?rev=142992&r1=142991&r2=142992&view=diff
==============================================================================
--- llvm/trunk/lib/VMCore/Instructions.cpp (original)
+++ llvm/trunk/lib/VMCore/Instructions.cpp Tue Oct 25 19:34:48 2011
@@ -1576,10 +1576,17 @@
         return false;
       }
     }
-  }
-  else if (!isa<UndefValue>(Mask) && !isa<ConstantAggregateZero>(Mask))
+  } else if (!isa<UndefValue>(Mask) && !isa<ConstantAggregateZero>(Mask)) {
+    // The bitcode reader can create a place holder for a forward reference
+    // used as the shuffle mask. When this occurs, the shuffle mask will
+    // fall into this case and fail. To avoid this error, do this bit of
+    // ugliness to allow such a mask pass.
+    if (const ConstantExpr* CE = dyn_cast<ConstantExpr>(Mask)) {
+      if (CE->getOpcode() == Instruction::UserOp1)
+        return true;
+    }
     return false;
-  
+  }
   return true;
 }
 

Added: llvm/trunk/test/Bitcode/shuffle.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Bitcode/shuffle.ll?rev=142992&view=auto
==============================================================================
--- llvm/trunk/test/Bitcode/shuffle.ll (added)
+++ llvm/trunk/test/Bitcode/shuffle.ll Tue Oct 25 19:34:48 2011
@@ -0,0 +1,31 @@
+; RUN: llvm-as < %s | llvm-dis
+
+; <rdar://problem/8622574>
+; tests the bitcodereader can handle the case where the reader will initially
+; create shuffle with a place holder mask.
+
+
+define <4 x float> @test(<2 x double> %d2)  {
+entry:
+  %call20.i = tail call <4 x float> @cmp(<2 x double> %d2,
+                                        <2 x double> bitcast (
+                                          <4 x float> shufflevector (
+                                            <3 x float> shufflevector (
+                                              <4 x float> shufflevector (
+                                                <3 x float> bitcast (
+                                                  i96 trunc (
+                                                    i128 bitcast (<2 x double> bitcast (
+                                                      <4 x i32> <i32 0, i32 0, i32 0, i32 undef> to <2 x double>)
+                                                    to i128) to i96)
+                                                  to <3 x float>),
+                                                <3 x float> undef,
+                                                <4 x i32> <i32 0, i32 1, i32 2, i32 undef>),
+                                              <4 x float> undef,
+                                            <3 x i32> <i32 0, i32 1, i32 2>),
+                                            <3 x float> undef,
+                                            <4 x i32> <i32 0, i32 1, i32 2, i32 undef>)
+                                          to <2 x double>))
+  ret <4 x float> %call20.i
+}
+
+declare <4 x float> @cmp(<2 x double>, <2 x double>)