Changes in directory llvm/lib/Target/X86:
X86RegisterInfo.cpp updated: 1.136 -> 1.137 --- Log message: We were not adjusting the frame size to ensure proper alignment when alloca / vla are present in the function. This causes a crash when a leaf function allocates space on the stack used to store / load with 128-bit SSE instructions. --- Diffs of the changes: (+23 -30) X86RegisterInfo.cpp | 53 ++++++++++++++++++++++------------------------------ 1 files changed, 23 insertions(+), 30 deletions(-) Index: llvm/lib/Target/X86/X86RegisterInfo.cpp diff -u llvm/lib/Target/X86/X86RegisterInfo.cpp:1.136 llvm/lib/Target/X86/X86RegisterInfo.cpp:1.137 --- llvm/lib/Target/X86/X86RegisterInfo.cpp:1.136 Mon Apr 10 02:21:31 2006 +++ llvm/lib/Target/X86/X86RegisterInfo.cpp Fri Apr 14 02:26:43 2006 @@ -573,17 +573,34 @@ // Get the number of bytes to allocate from the FrameInfo unsigned NumBytes = MFI->getStackSize(); + if (MFI->hasCalls() || MF.getFrameInfo()->hasVarSizedObjects()) { + // When we have no frame pointer, we reserve argument space for call sites + // in the function immediately on entry to the current function. This + // eliminates the need for add/sub ESP brackets around call sites. + // + if (!hasFP(MF)) + NumBytes += MFI->getMaxCallFrameSize(); + + // Round the size to a multiple of the alignment (don't forget the 4 byte + // offset though). + unsigned Align = MF.getTarget().getFrameInfo()->getStackAlignment(); + NumBytes = ((NumBytes+4)+Align-1)/Align*Align - 4; + } + + // Update frame info to pretend that this is part of the stack... + MFI->setStackSize(NumBytes); + + if (NumBytes) { // adjust stack pointer: ESP -= numbytes + unsigned Opc = NumBytes < 128 ? X86::SUB32ri8 : X86::SUB32ri; + MI = BuildMI(Opc, 1, X86::ESP,MachineOperand::UseAndDef).addImm(NumBytes); + MBB.insert(MBBI, MI); + } + if (hasFP(MF)) { // Get the offset of the stack slot for the EBP register... which is // guaranteed to be the last slot by processFunctionBeforeFrameFinalized. int EBPOffset = MFI->getObjectOffset(MFI->getObjectIndexBegin())+4; - if (NumBytes) { // adjust stack pointer: ESP -= numbytes - unsigned Opc = NumBytes < 128 ? X86::SUB32ri8 : X86::SUB32ri; - MI = BuildMI(Opc, 1, X86::ESP,MachineOperand::UseAndDef).addImm(NumBytes); - MBB.insert(MBBI, MI); - } - // Save EBP into the appropriate stack slot... MI = addRegOffset(BuildMI(X86::MOV32mr, 5), // mov [ESP-<offset>], EBP X86::ESP, EBPOffset+NumBytes).addReg(X86::EBP); @@ -596,30 +613,6 @@ MI = addRegOffset(BuildMI(X86::LEA32r, 5, X86::EBP), X86::ESP,NumBytes-4); MBB.insert(MBBI, MI); - - } else { - if (MFI->hasCalls()) { - // When we have no frame pointer, we reserve argument space for call sites - // in the function immediately on entry to the current function. This - // eliminates the need for add/sub ESP brackets around call sites. - // - NumBytes += MFI->getMaxCallFrameSize(); - - // Round the size to a multiple of the alignment (don't forget the 4 byte - // offset though). - unsigned Align = MF.getTarget().getFrameInfo()->getStackAlignment(); - NumBytes = ((NumBytes+4)+Align-1)/Align*Align - 4; - } - - // Update frame info to pretend that this is part of the stack... - MFI->setStackSize(NumBytes); - - if (NumBytes) { - // adjust stack pointer: ESP -= numbytes - unsigned Opc = NumBytes < 128 ? X86::SUB32ri8 : X86::SUB32ri; - MI= BuildMI(Opc, 1, X86::ESP, MachineOperand::UseAndDef).addImm(NumBytes); - MBB.insert(MBBI, MI); - } } } _______________________________________________ llvm-commits mailing list llvm-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits