llvm-6502/lib/Target/Mips/MipsModuleISelDAGToDAG.cpp

37 lines
1.0 KiB
C++
Raw Normal View History

This patch enables llvm to switch between compiling for mips32/mips64 and mips16 on a per function basis. Because this patch is somewhat involved I have provide an overview of the key pieces of it. The patch is written so as to not change the behavior of the non mixed mode. We have tested this a lot but it is something new to switch subtargets so we don't want any chance of regression in the mainline compiler until we have more confidence in this. Mips32/64 are very different from Mip16 as is the case of ARM vs Thumb1. For that reason there are derived versions of the register info, frame info, instruction info and instruction selection classes. Now we register three separate passes for instruction selection. One which is used to switch subtargets (MipsModuleISelDAGToDAG.cpp) and then one for each of the current subtargets (Mips16ISelDAGToDAG.cpp and MipsSEISelDAGToDAG.cpp). When the ModuleISel pass runs, it determines if there is a need to switch subtargets and if so, the owning pointers in MipsTargetMachine are appropriately changed. When 16Isel or SEIsel is run, they will return immediately without doing any work if the current subtarget mode does not apply to them. In addition, MipsAsmPrinter needs to be reset on a function basis. The pass BasicTargetTransformInfo is substituted with a null pass since the pass is immutable and really needs to be a function pass for it to be used with changing subtargets. This will be fixed in a follow on patch. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179118 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-09 19:46:01 +00:00
//===----------------------------------------------------------------------===//
// Instruction Selector Subtarget Control
//===----------------------------------------------------------------------===//
//===----------------------------------------------------------------------===//
// This file defines a pass used to change the subtarget for the
// Mips Instruction selector.
//
//===----------------------------------------------------------------------===//
#include "MipsISelDAGToDAG.h"
#include "MipsModuleISelDAGToDAG.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
[Modules] Make Support/Debug.h modular. This requires it to not change behavior based on other files defining DEBUG_TYPE, which means it cannot define DEBUG_TYPE at all. This is actually better IMO as it forces folks to define relevant DEBUG_TYPEs for their files. However, it requires all files that currently use DEBUG(...) to define a DEBUG_TYPE if they don't already. I've updated all such files in LLVM and will do the same for other upstream projects. This still leaves one important change in how LLVM uses the DEBUG_TYPE macro going forward: we need to only define the macro *after* header files have been #include-ed. Previously, this wasn't possible because Debug.h required the macro to be pre-defined. This commit removes that. By defining DEBUG_TYPE after the includes two things are fixed: - Header files that need to provide a DEBUG_TYPE for some inline code can do so by defining the macro before their inline code and undef-ing it afterward so the macro does not escape. - We no longer have rampant ODR violations due to including headers with different DEBUG_TYPE definitions. This may be mostly an academic violation today, but with modules these types of violations are easy to check for and potentially very relevant. Where necessary to suppor headers with DEBUG_TYPE, I have moved the definitions below the includes in this commit. I plan to move the rest of the DEBUG_TYPE macros in LLVM in subsequent commits; this one is big enough. The comments in Debug.h, which were hilariously out of date already, have been updated to reflect the recommended practice going forward. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206822 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-21 22:55:11 +00:00
#define DEBUG_TYPE "mips-isel"
This patch enables llvm to switch between compiling for mips32/mips64 and mips16 on a per function basis. Because this patch is somewhat involved I have provide an overview of the key pieces of it. The patch is written so as to not change the behavior of the non mixed mode. We have tested this a lot but it is something new to switch subtargets so we don't want any chance of regression in the mainline compiler until we have more confidence in this. Mips32/64 are very different from Mip16 as is the case of ARM vs Thumb1. For that reason there are derived versions of the register info, frame info, instruction info and instruction selection classes. Now we register three separate passes for instruction selection. One which is used to switch subtargets (MipsModuleISelDAGToDAG.cpp) and then one for each of the current subtargets (Mips16ISelDAGToDAG.cpp and MipsSEISelDAGToDAG.cpp). When the ModuleISel pass runs, it determines if there is a need to switch subtargets and if so, the owning pointers in MipsTargetMachine are appropriately changed. When 16Isel or SEIsel is run, they will return immediately without doing any work if the current subtarget mode does not apply to them. In addition, MipsAsmPrinter needs to be reset on a function basis. The pass BasicTargetTransformInfo is substituted with a null pass since the pass is immutable and really needs to be a function pass for it to be used with changing subtargets. This will be fixed in a follow on patch. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179118 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-09 19:46:01 +00:00
namespace llvm {
bool MipsModuleDAGToDAGISel::runOnMachineFunction(MachineFunction &MF) {
DEBUG(errs() << "In MipsModuleDAGToDAGISel::runMachineFunction\n");
const_cast<MipsSubtarget&>(Subtarget).resetSubtarget(&MF);
return false;
}
char MipsModuleDAGToDAGISel::ID = 0;
}
llvm::FunctionPass *llvm::createMipsModuleISelDag(MipsTargetMachine &TM) {
return new MipsModuleDAGToDAGISel(TM);
}