[NVPTX] Directly control the Machine SSA passes that are invoked for NVPTX.

NVPTX is a bit special in the optimizations it requires, so this gives
us better control over the backend optimization pipeline.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211927 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Justin Holewinski 2014-06-27 18:35:14 +00:00
parent a54609ed93
commit 7d7f3e3923

View File

@ -106,6 +106,7 @@ public:
bool addInstSelector() override;
bool addPreRegAlloc() override;
bool addPostRegAlloc() override;
void addMachineSSAOptimization() override;
FunctionPass *createTargetRegisterAllocator(bool) override;
void addFastRegAlloc(FunctionPass *RegAllocPass) override;
@ -207,3 +208,43 @@ void NVPTXPassConfig::addOptimizedRegAlloc(FunctionPass *RegAllocPass) {
printAndVerify("After StackSlotColoring");
}
void NVPTXPassConfig::addMachineSSAOptimization() {
// Pre-ra tail duplication.
if (addPass(&EarlyTailDuplicateID))
printAndVerify("After Pre-RegAlloc TailDuplicate");
// Optimize PHIs before DCE: removing dead PHI cycles may make more
// instructions dead.
addPass(&OptimizePHIsID);
// This pass merges large allocas. StackSlotColoring is a different pass
// which merges spill slots.
addPass(&StackColoringID);
// If the target requests it, assign local variables to stack slots relative
// to one another and simplify frame index references where possible.
addPass(&LocalStackSlotAllocationID);
// With optimization, dead code should already be eliminated. However
// there is one known exception: lowered code for arguments that are only
// used by tail calls, where the tail calls reuse the incoming stack
// arguments directly (see t11 in test/CodeGen/X86/sibcall.ll).
addPass(&DeadMachineInstructionElimID);
printAndVerify("After codegen DCE pass");
// Allow targets to insert passes that improve instruction level parallelism,
// like if-conversion. Such passes will typically need dominator trees and
// loop info, just like LICM and CSE below.
if (addILPOpts())
printAndVerify("After ILP optimizations");
addPass(&MachineLICMID);
addPass(&MachineCSEID);
addPass(&MachineSinkingID);
printAndVerify("After Machine LICM, CSE and Sinking passes");
addPass(&PeepholeOptimizerID);
printAndVerify("After codegen peephole optimization pass");
}