From 33b350bf24be396a127c81af045468765731afc7 Mon Sep 17 00:00:00 2001 From: Anton Korobeynikov Date: Thu, 16 Jul 2009 13:50:40 +0000 Subject: [PATCH] Scan for presence of calls and determine max callframe size early. To allow ProcessFunctionBeforeCalleeSaveScan() use this information git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75942 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/PrologEpilogInserter.cpp | 61 ++++++++++++++++------------ lib/CodeGen/PrologEpilogInserter.h | 1 + 2 files changed, 37 insertions(+), 25 deletions(-) diff --git a/lib/CodeGen/PrologEpilogInserter.cpp b/lib/CodeGen/PrologEpilogInserter.cpp index 2365316261b..970e395615d 100644 --- a/lib/CodeGen/PrologEpilogInserter.cpp +++ b/lib/CodeGen/PrologEpilogInserter.cpp @@ -59,14 +59,16 @@ bool PEI::runOnMachineFunction(MachineFunction &Fn) { if (MachineModuleInfo *MMI = getAnalysisIfAvailable()) Fn.getFrameInfo()->setMachineModuleInfo(MMI); + // Calculate the MaxCallFrameSize and HasCalls variables for the function's + // frame information. Also eliminates call frame pseudo instructions. + calculateCallsInformation(Fn); + // Allow the target machine to make some adjustments to the function // e.g. UsedPhysRegs before calculateCalleeSavedRegisters. TRI->processFunctionBeforeCalleeSavedScan(Fn, RS); - // Scan the function for modified callee saved registers and insert spill - // code for any callee saved registers that are modified. Also calculate - // the MaxCallFrameSize and HasCalls variables for the function's frame - // information and eliminates call frame pseudo instructions. + // Scan the function for modified callee saved registers and insert spill code + // for any callee saved registers that are modified. calculateCalleeSavedRegisters(Fn); // Determine placement of CSR spill/restore code: @@ -117,35 +119,24 @@ void PEI::getAnalysisUsage(AnalysisUsage &AU) const { } #endif -/// calculateCalleeSavedRegisters - Scan the function for modified callee saved -/// registers. Also calculate the MaxCallFrameSize and HasCalls variables for -/// the function's frame information and eliminates call frame pseudo -/// instructions. -/// -void PEI::calculateCalleeSavedRegisters(MachineFunction &Fn) { +/// calculateCallsInformation - Calculate the MaxCallFrameSize and HasCalls +/// variables for the function's frame information and eliminate call frame +/// pseudo instructions. +void PEI::calculateCallsInformation(MachineFunction &Fn) { const TargetRegisterInfo *RegInfo = Fn.getTarget().getRegisterInfo(); - const TargetFrameInfo *TFI = Fn.getTarget().getFrameInfo(); - // Get the callee saved register list... - const unsigned *CSRegs = RegInfo->getCalleeSavedRegs(&Fn); + unsigned MaxCallFrameSize = 0; + bool HasCalls = false; // Get the function call frame set-up and tear-down instruction opcode int FrameSetupOpcode = RegInfo->getCallFrameSetupOpcode(); int FrameDestroyOpcode = RegInfo->getCallFrameDestroyOpcode(); - // These are used to keep track the callee-save area. Initialize them. - MinCSFrameIndex = INT_MAX; - MaxCSFrameIndex = 0; - - // Early exit for targets which have no callee saved registers and no call - // frame setup/destroy pseudo instructions. - if ((CSRegs == 0 || CSRegs[0] == 0) && - FrameSetupOpcode == -1 && FrameDestroyOpcode == -1) + // Early exit for targets which have no call frame setup/destroy pseudo + // instructions. + if (FrameSetupOpcode == -1 && FrameDestroyOpcode == -1) return; - unsigned MaxCallFrameSize = 0; - bool HasCalls = false; - std::vector FrameSDOps; for (MachineFunction::iterator BB = Fn.begin(), E = Fn.end(); BB != E; ++BB) for (MachineBasicBlock::iterator I = BB->begin(); I != BB->end(); ++I) @@ -173,8 +164,28 @@ void PEI::calculateCalleeSavedRegisters(MachineFunction &Fn) { if (RegInfo->hasReservedCallFrame(Fn) || RegInfo->hasFP(Fn)) RegInfo->eliminateCallFramePseudoInstr(Fn, *I->getParent(), I); } +} + + +/// calculateCalleeSavedRegisters - Scan the function for modified callee saved +/// registers. +void PEI::calculateCalleeSavedRegisters(MachineFunction &Fn) { + const TargetRegisterInfo *RegInfo = Fn.getTarget().getRegisterInfo(); + const TargetFrameInfo *TFI = Fn.getTarget().getFrameInfo(); + MachineFrameInfo *FFI = Fn.getFrameInfo(); + + // Get the callee saved register list... + const unsigned *CSRegs = RegInfo->getCalleeSavedRegs(&Fn); + + // These are used to keep track the callee-save area. Initialize them. + MinCSFrameIndex = INT_MAX; + MaxCSFrameIndex = 0; + + // Early exit for targets which have no callee saved registers. + if (CSRegs == 0 || CSRegs[0] == 0) + return; - // Now figure out which *callee saved* registers are modified by the current + // Figure out which *callee saved* registers are modified by the current // function, thus needing to be saved and restored in the prolog/epilog. const TargetRegisterClass * const *CSRegClasses = RegInfo->getCalleeSavedRegClasses(&Fn); diff --git a/lib/CodeGen/PrologEpilogInserter.h b/lib/CodeGen/PrologEpilogInserter.h index c158dd8ac23..b143554e807 100644 --- a/lib/CodeGen/PrologEpilogInserter.h +++ b/lib/CodeGen/PrologEpilogInserter.h @@ -118,6 +118,7 @@ namespace llvm { CSRegBlockMap &prevRestores); void placeSpillsAndRestores(MachineFunction &Fn); void placeCSRSpillsAndRestores(MachineFunction &Fn); + void calculateCallsInformation(MachineFunction &Fn); void calculateCalleeSavedRegisters(MachineFunction &Fn); void insertCSRSpillsAndRestores(MachineFunction &Fn); void calculateFrameObjectOffsets(MachineFunction &Fn); -- 2.34.1