MWCC/compiler_and_linker/unsorted/IrOptimizer.c

#include "compiler/IrOptimizer.h"
#include "compiler/CError.h"
#include "compiler/CParser.h"
#include "compiler/InlineAsmPPC.h"
#include "compiler/IroCSE.h"
#include "compiler/IroDump.h"
#include "compiler/IroEval.h"
#include "compiler/IroFlowgraph.h"
#include "compiler/IroLinearForm.h"
#include "compiler/IroSubable.h"
#include "compiler/IroTransform.h"
#include "compiler/IROUseDef.h"
#include "compiler/IroUtil.h"
#include "compiler/IroVars.h"
#include "compiler/objects.h"
#include "compiler/IroPropagate.h"
#include "compiler/IroPointerAnalysis.h"
#include "compiler/IroJump.h"
#include "compiler/IroRangePropagation.h"
#include "compiler/IroEmptyLoop.h"
#include "compiler/IroUnrollLoop.h"
#include "compiler/IroLoop.h"
#include "compiler/IroExprRegeneration.h"

Boolean DoScalarize;
Boolean DoLinearize;
Boolean EarlyReturn;
Boolean IRO_CPFirstTime;
Boolean VectorPhaseCalledFromUnroll;
Boolean IRO_Log;
static Boolean stIsSetup;

static void CountRefToObject(Object *object, int depth) {
    static unsigned short LoopUsage[] = {1, 4, 16, 64};

    if (depth > 3)
        depth = 3;

    object->u.var.info->usage += LoopUsage[depth];
    object->u.var.info->used = 1;
}

static void CountARef(IROLinear *node, int depth) {
    Object *object;

    object = node->u.node->data.objref;
    CError_ASSERT(78, object->datatype != DALIAS);

    if (object->datatype == DLOCAL && object->u.var.info) {
        CountRefToObject(object, depth);
        if ((node->flags & IROLF_Used) && (node->flags & IROLF_Assigned))
            CountRefToObject(object, depth);

        if (!(node->flags & IROLF_Immind) && !object->u.var.info->noregister)
            object->u.var.info->noregister = 2;
    }
}

static void CountDoubleInd(IROLinear *node, int depth) {
    if (IRO_IsVariable(node)) {
        CountARef(node->u.monadic, depth);
    } else if (node->type == IROLinearOp2Arg) {
        if (node->nodetype == EADD) {
            CountDoubleInd(node->u.diadic.left, depth);
            CountDoubleInd(node->u.diadic.right, depth);
        } else if (IRO_IsAddressMultiply(node)) {
            if (IRO_IsVariable(node->u.diadic.left))
                CountARef(node->u.diadic.left->u.monadic, depth);
        }
    }
}

static void CountUsage(void) {
    IRONode *fnode = IRO_FirstNode;
    IROLinear *node;

    if (IRO_FirstNode) {
        for (; fnode; fnode = fnode->nextnode) {
            for (node = fnode->first; node; node = node->next) {
                if (IS_LINEAR_ENODE(node, EOBJREF))
                    CountARef(node, fnode->loopdepth);
                else if (IS_LINEAR_MONADIC(node, EINDIRECT))
                    CountDoubleInd(node->u.monadic, fnode->loopdepth);

                if (node->type == IROLinearAsm) {
                    IAEffects effects;
                    int i;

                    CodeGen_GetAsmEffects(node->u.asm_stmt, &effects);
                    for (i = 0; i < effects.numoperands; i++) {
                        Object *object = effects.operands[i].object;
                        if (object->datatype == DLOCAL && object->u.var.info) {
                            CountRefToObject(object, fnode->loopdepth);
                            if (effects.operands[i].type == IAOpnd_3 && !object->u.var.info->noregister)
                                object->u.var.info->noregister = 2;
                        }
                    }
                }

                if (node == fnode->last)
                    break;
            }
        }
    } else {
        for (node = IRO_FirstLinear; node; node = node->next) {
            if (IS_LINEAR_ENODE(node, EOBJREF))
                CountARef(node, 0);
            else if (IS_LINEAR_MONADIC(node, EINDIRECT))
                CountDoubleInd(node->u.monadic, 0);
        }
    }

    IRO_CheckForUserBreak();
}

Statement *IRO_Optimizer(Object *func, Statement *statements) {
    Boolean changed;
    Boolean changed2;
    int pass;
    int passCount;

    CError_ASSERT(234, stIsSetup);

#ifdef CW_PATCH_DEBUG
    if (copts.debuglisting)
        IRO_Log = 1;
#endif

    DisableDueToAsm = 0;
    FunctionName = func;
    DoScalarize = 1;
    DoLinearize = 1;
    EarlyReturn = 0;
    IRO_Depends = NULL;
    LoopOptimizerRun = 0;
    IRO_IsLeafFunction = 1;
    IRO_FunctionHasReturn = 0;

    IRO_SetupForUserBreakChecking();

    IRO_Dump("Starting function %s\n", func ? func->name->name : "Init-code");
    IRO_Dump("--------------------------------------------------------------------------------\n");

    if (DoLinearize)
        IRO_PreLinearize(statements);
    if (copts.optimizationlevel > 0)
        IRO_TransformTree(statements);

    VectorPhaseCalledFromUnroll = 0;

    IRO_Linearize(statements);

    CurStat = NULL;

    IRO_FirstExpr = NULL;
    IRO_LastExpr = NULL;
    IRO_FirstAssign = NULL;
    IRO_LastAssign = NULL;
    IRO_FirstVarUse = NULL;
    IRO_LastVarUse = NULL;
    IRO_FirstNode = NULL;
    IRO_LastNode = NULL;

    if (copts.optimizationlevel > 0)
        IRO_DoTransformations();

    IRO_BuildFlowgraph(IRO_FirstLinear);
    IRO_DumpAfterPhase("IRO_BuildflowGraph", 0);

    IRO_FindAllVars();
    IRO_CheckInit();

    if (!DisableDueToAsm && copts.optimizationlevel > 0 && copts.opt_pointer_analysis && func) {
        IRO_AnalyzePointers(func);
        if (copts.opt_propagation && IRO_EvaluateDefinitePointers(func)) {
            IRO_UpdateFlagsOnInts();
            IRO_UpdateVars();
            IRO_DumpAfterPhase("IRO_EvaluateDefinitePointers", 0);
        }
    }

    if (copts.optimizationlevel > 0) {
        changed = IRO_EvaluateConditionals();

        if (!DisableDueToAsm) {
            changed |= IRO_RemoveUnreachable();
            IRO_DumpAfterPhase("IRO_RemoveUnreachable", 0);
        }

        changed |= IRO_RemoveRedundantJumps();
        IRO_DumpAfterPhase("IRO_RemoveRedundantJumps", 0);

        if (!DisableDueToAsm) {
            changed |= IRO_RemoveLabels();
            IRO_DumpAfterPhase("IRO_RemoveLabels()", 0);
        }

        if (changed) {
            IRO_BuildFlowgraph(IRO_FirstLinear);
            IRO_DumpAfterPhase("IRO_BuildflowGraph--1", 0);
        }
    }

    if (!DisableDueToAsm && copts.optimizationlevel > 0) {
        passCount = copts._B4 ? 2 : 1;
        IRO_CPFirstTime = 1;
        for (pass = 0; pass < passCount; pass++) {
            IRO_Dump("*****************\n");
            IRO_Dump("Dumps for pass=%d\n", pass);
            IRO_Dump("*****************\n");

            if (DoScalarize)
                IRO_ScalarizeClassDataMembers();
            IRO_DumpAfterPhase("IRO_ScalarizeClassDataMembers", 0);

            if (copts.opt_propagation) {
                IRO_CopyAndConstantPropagation();
                IRO_CPFirstTime = 0;
                IRO_ExpressionPropagation();
                IRO_DumpAfterPhase("Copy and constant propagation", 0);

                IRO_RangePropagateInFNode();
                IRO_DumpAfterPhase("IRO_RangePropagateInFNode", 0);
                IRO_UpdateFlagsOnInts();
            }

            IRO_DumpAfterPhase("IRO_ExpressionPropagation", 0);

            if (copts.opt_dead_assignments || copts.opt_propagation)
                IRO_UseDef(copts.opt_dead_assignments, copts.opt_propagation);
            IRO_DumpAfterPhase("after IRO_UseDef", 0);

            IRO_UpdateVars();
            IRO_ConstantFolding();
            IRO_DumpAfterPhase("IRO_ConstantFolding", 0);

            IRO_EvaluateConditionals();
            IRO_RemoveUnreachable();
            IRO_SimplifyConditionals();

            if (pass == 1 && copts.optimizationlevel > 2) {
                IRO_RenumberInts();
                IRO_DumpAfterPhase("Before IRO_FindEmptyLoops", 0);
                IRO_FindEmptyLoops();
                IRO_DumpAfterPhase("After IRO_FindEmptyLoops", 0);
                IRO_RenumberInts();
            }

            if (copts.opt_unroll_loops && !copts.optimize_for_size && pass == 0) {
                IRO_DumpAfterPhase("Before IRO_LoopUnroller", 0);
                IRO_LoopUnroller();
                IRO_DumpAfterPhase("After IRO_LoopUnroller", 0);
                IRO_RenumberInts();
            }

            VectorPhaseCalledFromUnroll = 0;

            if (pass == 0 && (copts.opt_loop_invariants || copts.opt_strength_reduction)) {
                IRO_DumpAfterPhase("Before IRO_FindLoops", 0);
                IRO_FindLoops();
                LoopOptimizerRun = 1;
                IRO_SetLoopDepth();
            }
            IRO_DumpAfterPhase("After IRO_FindLoops", 0);

            if (copts.opt_propagation) {
                IRO_CopyAndConstantPropagation();
                IRO_ConstantFolding();
                IRO_EvaluateConditionals();
            }

            IRO_DumpAfterPhase("Second pass:IRO_CopyAndConstantPropagation, IRO_ConstantFolding, IRO_EvaluateConditionals", 0);

            if (copts.opt_common_subs)
                IRO_FindExpressions(NULL, 0);

            if (copts.opt_common_subs) {
                IRO_ComputeAvail();
                IRO_CommonSubs();
            }
            IRO_DumpAfterPhase("IRO_CommonSubs", 0);

            IRO_UpdateFlagsOnInts();
            IRO_UpdateVars();
            IRO_DoTransformations();
            IRO_ConstantFolding();

            do {
                IRO_UpdateFlagsOnInts();

                if (copts.opt_dead_code)
                    IRO_RemoveUnreachable();
                IRO_DumpAfterPhase("IRO_RemoveUnreachable", 0);

                changed2 = IRO_RemoveRedundantJumps();
                IRO_DumpAfterPhase("IRO_RemoveRedundantJumps", 0);

                changed2 |= IRO_RemoveLabels();
                IRO_DumpAfterPhase("IRO_RemoveLabels", 0);

                changed2 |= IRO_DoJumpChaining();
                IRO_DumpAfterPhase("IRO_DoJumpChaining", 0);

                if (copts.opt_propagation) {
                    IRO_RenumberInts();
                    IRO_DumpAfterPhase("Before IRO_CopyAndConstantPropagation", 0);
                    changed2 |= IRO_CopyAndConstantPropagation();
                    IRO_DumpAfterPhase("After IRO_CopyAndConstantPropagation", 0);
                    IRO_ConstantFolding();
                }

                if (copts.opt_dead_assignments || copts.opt_propagation)
                    changed2 |= IRO_UseDef(copts.opt_dead_assignments, copts.opt_propagation);
                IRO_DumpAfterPhase("IRO_UseDef", 0);

                changed2 |= IRO_EvaluateConditionals();
                IRO_DumpAfterPhase("IRO_EvaluateConditionals", 0);
            } while (changed2);
        }

        if (copts.opt_lifetimes) {
            IRO_UseDef(0, 0);
            IRO_SplitLifetimes();
        }

        IRO_DoTransformations();
        IRO_DumpAfterPhase("Before RebuildCondExpressions", 0);
    }

    IRO_RenumberInts();
    IRO_DumpAfterPhase("before IRO_RewriteBitFieldTemps", 0);
    IRO_RewriteBitFieldTemps();
    IRO_DumpAfterPhase("After IRO_RewriteBitFieldTemps", 0);

    CountUsage();

    if (!DisableDueToAsm) {
        IRO_RegenerateExpressions();
        IRO_DumpAfterPhase("IRO_RegenerateExpressions", 0);
    }

    IRO_DumpAfterPhase("After IRO_Optimizer", 0);

    statements = IRO_Delinearize(IRO_FirstNode, NULL);

    IRO_ZapVarPtrs();
    freeoheap();
    return statements;
}

void IRO_Setup(void) {
    static Boolean ENodeArraysHaveBeenInitialized;

    if (!stIsSetup) {
        IRO_Log = 0;
        IRO_SetupDump();
        if (!ENodeArraysHaveBeenInitialized) {
            IRO_InitializeNodeNamesArray();
            IRO_InitializeIsAssociativeENodeTypeArray();
            IRO_InitializeIsSubableOpArray();
            IRO_InitializeAssignmentOpArray();
            IRO_InitializeComplementaryOpArray();
            IRO_InitializeComplementaryOpLogicalArray();
            IRO_InitializeNonAssignmentOpArray();
            IRO_InitializeAssignmentFoldingFunctionArray();
            IRO_InitializeIRO_IsModifyOpArray();
            IRO_InitializeIRO_IsAssignOpArray();
            ENodeArraysHaveBeenInitialized = 1;
        }
        stIsSetup = 1;
    }
}

void IRO_Cleanup(void) {
    if (stIsSetup) {
        IRO_CleanupDump();
        stIsSetup = 0;
    }
}

void CodeGen_UpdateOptimizerOptions(void) {
    Boolean flag;

    flag = copts.optimizationlevel >= 1;
    copts.opt_dead_code = flag;

    flag = copts.optimizationlevel >= 2;
    copts.opt_propagation = flag;
    copts.opt_common_subs = flag;

    flag = copts.optimizationlevel >= 3;
    copts.opt_vectorize_loops = flag;
    copts.opt_unroll_loops = flag;
    copts.opt_dead_assignments = flag;
    copts.opt_lifetimes = flag;
    copts.opt_strength_reduction = flag;
    copts.opt_loop_invariants = flag;

    flag = copts.optimizationlevel >= 4;
    copts._B4 = flag;
}