LLVM  14.0.0git
Macros | Functions | Variables
R600OptimizeVectorRegisters.cpp File Reference
#include "MCTargetDesc/R600MCTargetDesc.h"
#include "R600.h"
#include "R600Defines.h"
#include "R600Subtarget.h"
#include "llvm/CodeGen/MachineDominators.h"
#include "llvm/CodeGen/MachineLoopInfo.h"
Include dependency graph for R600OptimizeVectorRegisters.cpp:

Go to the source code of this file.

Macros

#define DEBUG_TYPE   "vec-merger"
 

Functions

static bool isImplicitlyDef (MachineRegisterInfo &MRI, Register Reg)
 
 INITIALIZE_PASS_BEGIN (R600VectorRegMerger, DEBUG_TYPE, "R600 Vector Reg Merger", false, false) INITIALIZE_PASS_END(R600VectorRegMerger
 
static unsigned getReassignedChan (const std::vector< std::pair< unsigned, unsigned >> &RemapChan, unsigned Chan)
 

Variables

 DEBUG_TYPE
 
R600 Vector Reg Merger
 
R600 Vector Reg false
 

Detailed Description

This pass merges inputs of swizzeable instructions into vector sharing common data and/or have enough undef subreg using swizzle abilities.

For instance let's consider the following pseudo code : %5 = REG_SEQ %1, sub0, %2, sub1, %3, sub2, undef, sub3 ... %7 = REG_SEQ %1, sub0, %3, sub1, undef, sub2, %4, sub3 (swizzable Inst) %7, SwizzleMask : sub0, sub1, sub2, sub3

is turned into : %5 = REG_SEQ %1, sub0, %2, sub1, %3, sub2, undef, sub3 ... %7 = INSERT_SUBREG %4, sub3 (swizzable Inst) %7, SwizzleMask : sub0, sub2, sub1, sub3

This allow regalloc to reduce register pressure for vector registers and to reduce MOV count.

Definition in file R600OptimizeVectorRegisters.cpp.

Macro Definition Documentation

◆ DEBUG_TYPE

#define DEBUG_TYPE   "vec-merger"

Definition at line 38 of file R600OptimizeVectorRegisters.cpp.

Function Documentation

◆ getReassignedChan()

static unsigned getReassignedChan ( const std::vector< std::pair< unsigned, unsigned >> &  RemapChan,
unsigned  Chan 
)
static

Definition at line 172 of file R600OptimizeVectorRegisters.cpp.

References j(), and llvm_unreachable.

◆ INITIALIZE_PASS_BEGIN()

INITIALIZE_PASS_BEGIN ( R600VectorRegMerger  ,
DEBUG_TYPE  ,
"R600 Vector Reg Merger ,
false  ,
false   
)

◆ isImplicitlyDef()

static bool isImplicitlyDef ( MachineRegisterInfo MRI,
Register  Reg 
)
static

Variable Documentation

◆ DEBUG_TYPE

DEBUG_TYPE

Definition at line 129 of file R600OptimizeVectorRegisters.cpp.

◆ false

R600 Vector Reg false

Definition at line 130 of file R600OptimizeVectorRegisters.cpp.

◆ Merger

R600 Vector Reg Merger

Definition at line 130 of file R600OptimizeVectorRegisters.cpp.