Change StackDirection from StackGrowsUp to StackGrowsDown.
The following improvements are accomplished as a result of applying this patch:
- Fixed frame objects' offsets (relative to either the virtual frame pointer or
the stack pointer) are set before instruction selection is completed. There is
no need to wait until Prologue/Epilogue Insertion is run to set them.
- Calculation of final offsets of fixed frame objects is straightforward. It is
no longer necessary to assign negative offsets to fixed objects for incoming
arguments in order to distinguish them from the others.
- Since a fixed object has its relative offset set during instruction
selection, there is no need to conservatively set its alignment to 4.
- It is no longer necessary to reorder non-fixed frame objects in
MipsFrameLowering::adjustMipsStackFrame.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131915 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/Mips/MipsISelLowering.cpp b/lib/Target/Mips/MipsISelLowering.cpp
index 0ffceeb..dda7e8d 100644
--- a/lib/Target/Mips/MipsISelLowering.cpp
+++ b/lib/Target/Mips/MipsISelLowering.cpp
@@ -1069,7 +1069,7 @@
// Create GP frame object if this is the first call.
// SPOffset will be updated after call frame size is known.
- if (IsPIC && MipsFI->getGPStackOffset() == -1)
+ if (IsPIC && !MipsFI->getGPFI())
MipsFI->setGPFI(MFI->CreateFixedObject(4, 0, true));
int FirstFI = -MFI->getNumFixedObjects() - 1, LastFI = 0;
@@ -1124,10 +1124,10 @@
// This guarantees that when allocating Local Area the firsts
// 16 bytes which are alwayes reserved won't be overwritten
// if O32 ABI is used. For EABI the first address is zero.
+ unsigned ArgSize = VA.getValVT().getSizeInBits()/8;
NextStackOffset = VA.getLocMemOffset();
- LastFI = MFI->CreateFixedObject(VA.getValVT().getSizeInBits()/8,
- NextStackOffset, true);
- NextStackOffset += VA.getValVT().getSizeInBits()/8;
+ LastFI = MFI->CreateFixedObject(ArgSize, NextStackOffset, true);
+ NextStackOffset += ArgSize;
SDValue PtrOff = DAG.getFrameIndex(LastFI, getPointerTy());
@@ -1243,7 +1243,8 @@
unsigned StackAlignment = TFL->getStackAlignment();
NextStackOffset = (NextStackOffset + StackAlignment - 1) /
StackAlignment * StackAlignment;
- MipsFI->setGPStackOffset(NextStackOffset);
+ int GPFI = MipsFI->getGPFI();
+ MFI->setObjectOffset(GPFI, NextStackOffset);
}
}
@@ -1405,9 +1406,9 @@
// be used on emitPrologue) to avoid mis-calc of the first stack
// offset on PEI::calculateFrameObjectOffsets.
unsigned ArgSize = VA.getValVT().getSizeInBits()/8;
- NextStackOffset = VA.getLocMemOffset() + ArgSize;
- LastFI = MFI->CreateFixedObject(ArgSize, 0, true);
- MipsFI->recordLoadArgsFI(LastFI, -(4 + VA.getLocMemOffset()));
+ NextStackOffset = VA.getLocMemOffset();
+ LastFI = MFI->CreateFixedObject(ArgSize, NextStackOffset, true);
+ NextStackOffset += ArgSize;
// Create load nodes to retrieve arguments from the stack
SDValue FIN = DAG.getFrameIndex(LastFI, getPointerTy());
@@ -1449,8 +1450,7 @@
unsigned Reg = AddLiveIn(DAG.getMachineFunction(), ArgRegEnd, RC);
SDValue ArgValue = DAG.getCopyFromReg(Chain, dl, Reg, MVT::i32);
- LastFI = MFI->CreateFixedObject(4, 0, true);
- MipsFI->recordStoreVarArgsFI(LastFI, -(4+(ArgRegEnd-Mips::A0)*4));
+ LastFI = MFI->CreateFixedObject(4, (ArgRegEnd-Mips::A0)*4, true);
SDValue PtrOff = DAG.getFrameIndex(LastFI, getPointerTy());
OutChains.push_back(DAG.getStore(Chain, dl, ArgValue, PtrOff,
MachinePointerInfo(),
@@ -1458,26 +1458,20 @@
// Record the frame index of the first variable argument
// which is a value necessary to VASTART.
- if (!MipsFI->getVarArgsFrameIndex()) {
- MFI->setObjectAlignment(LastFI, 4);
+ if (!MipsFI->getVarArgsFrameIndex())
MipsFI->setVarArgsFrameIndex(LastFI);
- }
}
} else {
// Last named formal argument is in register Mips::A3, and the first
// variable argument is on stack. Record the frame index of the first
// variable argument.
- LastFI = MFI->CreateFixedObject(4, 0, true);
- MFI->setObjectAlignment(LastFI, 4);
- MipsFI->recordStoreVarArgsFI(LastFI, -20);
+ LastFI = MFI->CreateFixedObject(4, 16, true);
MipsFI->setVarArgsFrameIndex(LastFI);
}
} else {
// Last named formal argument and all the variable arguments are passed
// on stack. Record the frame index of the first variable argument.
- LastFI = MFI->CreateFixedObject(4, 0, true);
- MFI->setObjectAlignment(LastFI, 4);
- MipsFI->recordStoreVarArgsFI(LastFI, -(4+NextStackOffset));
+ LastFI = MFI->CreateFixedObject(4, NextStackOffset, true);
MipsFI->setVarArgsFrameIndex(LastFI);
}
}