[llvm-commits] [llvm] r84954 - in /llvm/trunk: lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp test/CodeGen/X86/large-gep-scale.ll

[Dan Gohman]

Author: djg
Date: Fri Oct 23 12:57:43 2009
New Revision: 84954

URL: http://llvm.org/viewvc/llvm-project?rev=84954&view=rev
Log:
APInt-ify the gep scaling code, so that it correctly handles the case where
the scale overflows pointer-sized arithmetic. This fixes PR5281.

Added:
    llvm/trunk/test/CodeGen/X86/large-gep-scale.ll
Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp?rev=84954&r1=84953&r2=84954&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp Fri Oct 23 12:57:43 2009
@@ -2666,7 +2666,8 @@
       }
 
       // N = N + Idx * ElementSize;
-      uint64_t ElementSize = TD->getTypeAllocSize(Ty);
+      APInt ElementSize = APInt(TLI.getPointerTy().getSizeInBits(),
+                                TD->getTypeAllocSize(Ty));
       SDValue IdxN = getValue(Idx);
 
       // If the index is smaller or larger than intptr_t, truncate or extend
@@ -2676,13 +2677,13 @@
       // If this is a multiply by a power of two, turn it into a shl
       // immediately.  This is a very common case.
       if (ElementSize != 1) {
-        if (isPowerOf2_64(ElementSize)) {
-          unsigned Amt = Log2_64(ElementSize);
+        if (ElementSize.isPowerOf2()) {
+          unsigned Amt = ElementSize.logBase2();
           IdxN = DAG.getNode(ISD::SHL, getCurDebugLoc(),
                              N.getValueType(), IdxN,
                              DAG.getConstant(Amt, TLI.getPointerTy()));
         } else {
-          SDValue Scale = DAG.getIntPtrConstant(ElementSize);
+          SDValue Scale = DAG.getConstant(ElementSize, TLI.getPointerTy());
           IdxN = DAG.getNode(ISD::MUL, getCurDebugLoc(),
                              N.getValueType(), IdxN, Scale);
         }

Added: llvm/trunk/test/CodeGen/X86/large-gep-scale.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/large-gep-scale.ll?rev=84954&view=auto

==============================================================================
--- llvm/trunk/test/CodeGen/X86/large-gep-scale.ll (added)
+++ llvm/trunk/test/CodeGen/X86/large-gep-scale.ll Fri Oct 23 12:57:43 2009
@@ -0,0 +1,12 @@
+; RUN: llc < %s -march=x86 | FileCheck %s
+; PR5281
+
+; After scaling, this type doesn't fit in memory. Codegen should generate
+; correct addressing still.
+
+; CHECK: shll $2, %edx
+
+define fastcc i32* @_ada_smkr([2147483647 x i32]* %u, i32 %t) nounwind {
+  %x = getelementptr [2147483647 x i32]* %u, i32 %t, i32 0
+  ret i32* %x
+}