[llvm-commits] [llvm] r155753 - /llvm/trunk/lib/Target/ARM/ARMConstantIslandPass.cpp

[Jakob Stoklund Olesen]

Author: stoklund
Date: Sat Apr 28 01:21:38 2012
New Revision: 155753

URL: http://llvm.org/viewvc/llvm-project?rev=155753&view=rev
Log:
Fix a problem with blocks that need to be split twice.

The code could search past the end of the basic block when there was
already a constant pool entry after the block.

Test case with giant basic block in SingleSource/UnitTests/Vector/constpool.c

Modified:
    llvm/trunk/lib/Target/ARM/ARMConstantIslandPass.cpp

Modified: llvm/trunk/lib/Target/ARM/ARMConstantIslandPass.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMConstantIslandPass.cpp?rev=155753&r1=155752&r2=155753&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMConstantIslandPass.cpp (original)
+++ llvm/trunk/lib/Target/ARM/ARMConstantIslandPass.cpp Sat Apr 28 01:21:38 2012
@@ -1301,9 +1301,10 @@
   // pool entries following this block; only the last one is in the water list.
   // Back past any possible branches (allow for a conditional and a maximally
   // long unconditional).
-  if (BaseInsertOffset >= BBInfo[UserMBB->getNumber()+1].Offset)
-    BaseInsertOffset = BBInfo[UserMBB->getNumber()+1].Offset -
-      (isThumb1 ? 6 : 8);
+  if (BaseInsertOffset + 8 >= UserBBI.postOffset()) {
+    BaseInsertOffset = UserBBI.postOffset() - UPad - 8;
+    DEBUG(dbgs() << format("Move inside block: %#x\n", BaseInsertOffset));
+  }
   unsigned EndInsertOffset = BaseInsertOffset + 4 + UPad +
     CPEMI->getOperand(2).getImm();
   MachineBasicBlock::iterator MI = UserMI;
@@ -1315,6 +1316,7 @@
        Offset < BaseInsertOffset;
        Offset += TII->GetInstSizeInBytes(MI),
        MI = llvm::next(MI)) {
+    assert(MI != UserMBB->end() && "Fell off end of block");
     if (CPUIndex < NumCPUsers && CPUsers[CPUIndex].MI == MI) {
       CPUser &U = CPUsers[CPUIndex];
       if (!isOffsetInRange(Offset, EndInsertOffset, U)) {