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-rw-r--r--compiler_and_linker/unsorted/IroEmptyLoop.c560
1 files changed, 0 insertions, 560 deletions
diff --git a/compiler_and_linker/unsorted/IroEmptyLoop.c b/compiler_and_linker/unsorted/IroEmptyLoop.c
deleted file mode 100644
index 1e319ab..0000000
--- a/compiler_and_linker/unsorted/IroEmptyLoop.c
+++ /dev/null
@@ -1,560 +0,0 @@
-#include "compiler/IroEmptyLoop.h"
-#include "compiler/IroDump.h"
-#include "compiler/IroFlowgraph.h"
-#include "compiler/IroLinearForm.h"
-#include "compiler/IroLoop.h"
-#include "compiler/IroUtil.h"
-#include "compiler/IroVars.h"
-#include "compiler/CInt64.h"
-
-// forward decls
-static Boolean EmptyLoop(IRONode *fnode);
-static int CanRemoveRedundantLoop(IROLoop *loop);
-static int CanRemoveRedundantLoop1(IROLoop *loop);
-static int RedundantLoopCheck(IROLoop *loop);
-static int CheckStepOverFlow1_EmptyLoop(IROLoop *loop, CInt64 *val1, CInt64 *val2);
-static int CheckStepOverFlow2_EmptyLoop(IROLoop *loop, CInt64 *val1, CInt64 *val2);
-
-void IRO_FindEmptyLoops(void) {
- IRONode *fnode;
- IRONode *pred;
- UInt16 i;
- UInt16 x;
-
- for (fnode = IRO_FirstNode; fnode; fnode = fnode->nextnode) {
- x = 0;
- for (i = 0; i < fnode->numpred; i++) {
- pred = IRO_NodeTable[fnode->pred[i]];
- if (Bv_IsBitSet(fnode->index, pred->dom)) {
- if (!x) {
- Bv_AllocVector(&InLoop, IRO_NumNodes + 1);
- Bv_Clear(InLoop);
- Bv_SetBit(fnode->index, InLoop);
- }
- x = 1;
- Bv_SetBit(pred->index, InLoop);
- if (pred != fnode)
- AddPreds(pred);
- }
- }
-
- if (x) {
- IRO_Dump("IRO_FindEmptyLoops:Found loop with header %d\n", fnode->index);
- IRO_DumpBits("Loop includes: ", InLoop);
- EmptyLoop(fnode);
- IRO_UpdateFlagsOnInts();
- }
- }
-
- IRO_CheckForUserBreak();
-}
-
-static Boolean EmptyLoop(IRONode *fnode) {
- VarRecord *var;
- IRONode *bestpred;
- IRONode *pred;
- UInt16 i;
- int flag2;
- IRONode *r24;
- Boolean flag;
- int counter;
- int j;
- IRONode *succ;
- IRONode *bestsucc;
- int counter2;
- UInt32 counter3;
- IROLoop *loop;
- IRONode *r21;
- IRONode *r20;
- IROLinear *constnd;
- Type *type20;
- ENode *enode;
- IROLinear *save;
-
- flag = 0;
- counter = 0;
- LoopNode = fnode;
- FindMustReach();
-
- for (var = IRO_FirstVar; var; var = var->next)
- var->xA = 1;
-
- ComputeLoopKills();
- ComputeLoopInvariance();
- ComputeLoopInduction();
-
- LoopNode = fnode;
- ConditionalHeaderAtBottom = 0;
-
- bestpred = NULL;
- flag2 = 0;
- for (i = 0; i < LoopNode->numpred; i++) {
- pred = IRO_NodeTable[LoopNode->pred[i]];
- if (!Bv_IsBitSet(pred->index, InLoop)) {
- flag2 = 1;
- if (pred->nextnode == fnode) {
- CError_ASSERT(173, !bestpred || pred == bestpred);
- bestpred = pred;
- }
- }
- }
-
- if (!flag2) {
- IRO_Dump("No predecessor outside the loop\n");
- return 0;
- }
-
- bestsucc = NULL;
- for (i = 0; i < LoopNode->numsucc; i++) {
- succ = IRO_NodeTable[LoopNode->succ[i]];
- if (Bv_IsBitSet(succ->index, InLoop)) {
- bestsucc = succ;
- counter++;
- }
- }
-
- if (LoopNode == bestsucc && counter == 1)
- flag = 1;
-
- if (LoopNode->last->type != IROLinearIf || LoopNode->last->type != IROLinearIfNot || flag) {
- counter2 = 0;
- for (j = 0; j < LoopNode->numpred; j++) {
- if (Bv_IsBitSet(IRO_NodeTable[LoopNode->pred[j]]->index, InLoop)) {
- r21 = IRO_NodeTable[LoopNode->pred[j]];
- counter2++;
- }
- }
-
- r24 = NULL;
- counter3 = 0;
- for (j = 0; j < LoopNode->numpred; j++) {
- if (!Bv_IsBitSet(IRO_NodeTable[LoopNode->pred[j]]->index, InLoop)) {
- r24 = IRO_NodeTable[LoopNode->pred[j]];
- counter3++;
- }
- }
-
- if (counter2 == 1 && counter3 == 1) {
- if (r21->last->type == IROLinearIf) {
- if ((Bv_IsBitSet(LoopNode->nextnode->index, InLoop) && !Bv_IsBitSet(r21->nextnode->index, InLoop)) || flag) {
- IRO_Dump("Standard while loop layout\n");
- loop = ExtractLoopInfo(r21);
- if (flag)
- loop->flags |= LoopFlags_20000;
- FindAssignmenttoInductionVar(loop, r24);
- r20 = r24;
- while (r20 && !loop->nd14 && r20->numpred == 1 && IRO_NodeTable[r20->pred[0]]->numsucc == 1) {
- FindAssignmenttoInductionVar(loop, IRO_NodeTable[r20->pred[0]]);
- r20 = IRO_NodeTable[r20->pred[0]];
- }
-
- if (CanRemoveRedundantLoop(loop)) {
- IRO_Dump("EmptyLoop: # of iterations =%" PRId32 ", FinalStoreVal=%" PRId32 "\n", CInt64_GetULong(&loop->x28), CInt64_GetULong(&loop->x30));
- IRO_NopOut(r21->last->u.label.x4);
- r21->last->type = IROLinearNop;
- type20 = loop->induction->nd->rtype;
- constnd = IRO_NewLinear(IROLinearOperand);
- constnd->index = ++IRO_NumLinear;
- enode = IRO_NewENode(EINTCONST);
- enode->rtype = type20;
- enode->data.intval = loop->x30;
- constnd->u.node = enode;
- constnd->rtype = type20;
-
- if (loop->induction->nd->type == IROLinearOp1Arg) {
- save = loop->induction->nd->u.monadic;
- loop->induction->nd->type = IROLinearOp2Arg;
- loop->induction->nd->nodetype = EASS;
- loop->induction->nd->u.diadic.left = save;
- loop->induction->nd->u.diadic.right = constnd;
- IRO_Paste(constnd, constnd, loop->induction->nd);
- } else if (loop->induction->nd->type == IROLinearOp2Arg) {
- loop->induction->nd->nodetype = EASS;
- IRO_NopOut(loop->induction->nd->u.diadic.right);
- loop->induction->nd->u.diadic.right = constnd;
- IRO_Paste(constnd, constnd, loop->induction->nd);
- }
- } else if (CanRemoveRedundantLoop1(loop)) {
- IRO_Dump("EmptyLoop: self recursive dowhile(--n ) loop\n");
-
- r21->last->type = IROLinearNop;
- type20 = loop->induction->nd->rtype;
- constnd = IRO_NewLinear(IROLinearOperand);
- constnd->index = ++IRO_NumLinear;
- enode = IRO_NewENode(EINTCONST);
- enode->rtype = type20;
- enode->data.intval = cint64_zero;
- constnd->u.node = enode;
- constnd->rtype = type20;
-
- save = loop->induction->nd->u.monadic;
- loop->induction->nd->type = IROLinearOp2Arg;
- loop->induction->nd->nodetype = EASS;
- loop->induction->nd->u.diadic.left = save;
- loop->induction->nd->u.diadic.right = constnd;
- IRO_Paste(constnd, constnd, loop->induction->nd);
- }
- } else {
- IRO_Dump("NonStandard while loop layout\n");
- }
- } else {
- IRO_Dump("NonStandard while loop layout\n");
- }
- } else {
- IRO_Dump("Cannot handle Do While Loop with multiple tails\n");
- }
- }
-
- return 0;
-}
-
-static int CanRemoveRedundantLoop(IROLoop *loop) {
- IROLinear *inner;
-
- if (loop->flags & LoopFlags_10000) {
- IRO_Dump("CanRemoveRedundantLoop:No because detection of dowhile(n--) loop not supported\n");
- return 0;
- }
-
- if (loop->flags & LP_LOOP_HAS_ASM) {
- IRO_Dump("CanRemoveRedundantLoop:No due to LP_LOOP_HAS_ASM \n");
- return 0;
- }
-
- if (loop->flags & LP_IFEXPR_NON_CANONICAL) {
- IRO_Dump("CanRemoveRedundantLoop:No due to LP_IFEXPR_NON_CANONICAL \n");
- return 0;
- }
-
- if (loop->flags & LP_LOOP_HAS_CALLS) {
- IRO_Dump("CanRemoveRedundantLoop:No due to LP_LOOP_HAS_CALLS \n");
- return 0;
- }
-
- if (loop->flags & LP_LOOP_HAS_CNTRLFLOW) {
- IRO_Dump("CanRemoveRedundantLoop:No due to LP_LOOP_HAS_CNTRLFLOW \n");
- return 0;
- }
-
- if (loop->flags & LP_INDUCTION_NOT_FOUND) {
- IRO_Dump("CanRemoveRedundantLoop:No due to LP_INDUCTION_NOT_FOUND \n");
- return 0;
- }
-
- if (loop->flags & LP_HAS_MULTIPLE_INDUCTIONS) {
- IRO_Dump("CanRemoveRedundantLoop:No due to LP_HAS_MULTIPLE_INDUCTIONS \n");
- return 0;
- }
-
- if (loop->flags & LP_LOOP_HDR_HAS_SIDEEFFECTS) {
- IRO_Dump("CanRemoveRedundantLoop:No due to LP_LOOP_HDR_HAS_SIDEEFFECTS \n");
- return 0;
- }
-
- if (!(loop->flags & LoopFlags_200)) {
- IRO_Dump("CanRemoveRedundantLoop:No because header does not follow induction update \n");
- return 0;
- }
-
- if (!(loop->flags & LoopFlags_10000)) {
- inner = loop->nd18->u.diadic.right;
- if (!IRO_IsIntConstant(inner) && !(inner->flags & IROLF_LoopInvariant)) {
- IRO_Dump("CanRemoveRedundantLoop:No because Loop Upper Bound is Variant in the loop\n");
- return 0;
- }
-
- if (!loop->nd14) {
- IRO_Dump("CanRemoveRedundantLoop:No because there is no initialization of loop index in PreHeader\n");
- return 0;
- }
-
- if (!IRO_IsVariable(loop->nd14->u.diadic.left)) {
- IRO_Dump("CanRemoveRedundantLoop:No because initial value of induction stored thru pointer\n");
- return 0;
- }
-
- if (!IRO_IsUnsignedType(loop->nd14->rtype)) {
- if (IRO_IsIntConstant(loop->nd14->u.diadic.right)) {
- if (!CInt64_GreaterEqual(loop->nd14->u.diadic.right->u.node->data.intval, cint64_zero)) {
- IRO_Dump("CanRemoveRedundantLoop:No because initial value of induction is signed but < 0\n");
- return 0;
- }
- } else {
- IRO_Dump("CanRemoveRedundantLoop:No because initial value of induction is signed and not constant\n");
- return 0;
- }
- }
-
- if (!(loop->flags & LP_LOOP_STEP_ISPOS) && !(loop->flags & LP_LOOP_STEP_ISNEG)) {
- IRO_Dump("CanRemoveRedundantLoop:No because LP_LOOP_STEP_ISPOS/LP_LOOP_STEP_ISNEG is not set\n");
- return 0;
- }
-
- if ((loop->flags & LP_LOOP_STEP_ISPOS) && CheckStepOverFlow1_EmptyLoop(loop, &loop->x28, &loop->x30)) {
- IRO_Dump("CanRemoveRedundantLoop:No because Final Value of indution will overflow\n");
- return 0;
- }
-
- if ((loop->flags & LP_LOOP_STEP_ISNEG) && CheckStepOverFlow2_EmptyLoop(loop, &loop->x28, &loop->x30)) {
- IRO_Dump("CanRemoveRedundantLoop:No because Final Value of indution will overflow\n");
- return 0;
- }
- }
-
- return RedundantLoopCheck(loop) != 0;
-}
-
-static int CanRemoveRedundantLoop1(IROLoop *loop) {
- if ((loop->flags & LoopFlags_10000) && (loop->flags & LoopFlags_20000)) {
- if (loop->flags & LP_LOOP_HAS_ASM) {
- IRO_Dump("CanRemoveRedundantLoop1:No due to LP_LOOP_HAS_ASM \n");
- return 0;
- }
-
- if (loop->flags & LP_IFEXPR_NON_CANONICAL) {
- IRO_Dump("CanRemoveRedundantLoop1:No due to LP_IFEXPR_NON_CANONICAL \n");
- return 0;
- }
-
- if (loop->flags & LP_LOOP_HAS_CALLS) {
- IRO_Dump("CanRemoveRedundantLoop1:No due to LP_LOOP_HAS_CALLS \n");
- return 0;
- }
-
- if (loop->flags & LP_LOOP_HAS_CNTRLFLOW) {
- IRO_Dump("CanRemoveRedundantLoop1:No due to LP_LOOP_HAS_CNTRLFLOW \n");
- return 0;
- }
-
- if (loop->flags & LP_INDUCTION_NOT_FOUND) {
- IRO_Dump("CanRemoveRedundantLoop1:No due to LP_INDUCTION_NOT_FOUND \n");
- return 0;
- }
-
- if (loop->flags & LP_HAS_MULTIPLE_INDUCTIONS) {
- IRO_Dump("CanRemoveRedundantLoop1:No due to LP_HAS_MULTIPLE_INDUCTIONS \n");
- return 0;
- }
-
- if (loop->flags & LP_LOOP_HDR_HAS_SIDEEFFECTS) {
- IRO_Dump("CanRemoveRedundantLoop1:No due to LP_LOOP_HDR_HAS_SIDEEFFECTS \n");
- return 0;
- }
-
- if (!(loop->flags & LoopFlags_200)) {
- IRO_Dump("CanRemoveRedundantLoop1:No because header does not follow induction update \n");
- return 0;
- }
-
- if (loop->induction->nd->type == IROLinearOp1Arg && loop->induction->nd->nodetype == EPREDEC) {
- if (IRO_IsUnsignedType(loop->induction->nd->rtype))
- return 1;
- IRO_Dump("CanRemoveRedundantLoop1:No because induction not of the right type \n");
- return 0;
- }
-
- IRO_Dump("CanRemoveRedundantLoop1:No because induction operator not a predec \n");
- return 0;
- } else {
- return 0;
- }
-}
-
-static int RedundantLoopCheck(IROLoop *loop) {
- IRONode *fnode;
- IROLinear *nd;
-
- for (fnode = IRO_FirstNode; fnode; fnode = fnode->nextnode) {
- if (Bv_IsBitSet(fnode->index, InLoop) && fnode != loop->fnode && (nd = fnode->first)) {
- while (1) {
- if ((nd->index < loop->index20 || nd->index > loop->index24) && nd->type != IROLinearNop && nd->type != IROLinearLabel) {
- if (IS_LINEAR_DIADIC(nd, EASS)) {
- if (!(nd->flags & IROLF_Reffed)) {
- if (IS_LINEAR_MONADIC(nd->u.diadic.left, EINDIRECT)) {
- if (nd->u.diadic.left->rtype && CParser_IsVolatile(nd->u.diadic.left->rtype, nd->u.diadic.left->nodeflags & ENODE_FLAG_QUALS)) {
- IRO_Dump(" EASS at %d fail as store to volatile memory \n", nd->index);
- return 0;
- }
-
- if ((nd->u.diadic.left->u.monadic->flags & IROLF_LoopInvariant) && (nd->u.diadic.right->flags & IROLF_LoopInvariant)) {
- IRO_Dump(" EASS at %d pass\n", nd->index);
- } else {
- IRO_Dump(" EASS at %d fail, either LHS address or RHS is variant \n", nd->index);
- return 0;
- }
- } else {
- IRO_Dump("Found EASS nodes whose lhs root is not a EINDIRECT node\n");
- return 0;
- }
- } else {
- IRO_Dump("Found EASS node that is referenced i.e embedded assignment\n");
- return 0;
- }
- } else {
- if (!(nd->flags & IROLF_Reffed)) {
- IRO_Dump("Found non EASS top level node in the loop\n");
- return 0;
- }
- }
- }
-
- if (nd == fnode->last)
- break;
- nd = nd->next;
- }
- }
- }
-
- return 1;
-}
-
-static int CheckStepOverFlow1_EmptyLoop(IROLoop *loop, CInt64 *val1, CInt64 *val2) {
- Boolean isUnsigned;
- IROLinear *nd2;
- IROLinear *nd1;
- CInt64 nd2value;
- CInt64 nd1value;
- CInt64 addConst;
- CInt64 work;
- CInt64 neg1;
-
- nd2 = loop->nd14->u.diadic.right;
- nd1 = loop->nd18->u.diadic.right;
- isUnsigned = IRO_IsUnsignedType(loop->nd18->u.diadic.right->rtype);
-
- if (IRO_IsIntConstant(nd2) && IRO_IsIntConstant(nd1)) {
- nd2value = nd2->u.node->data.intval;
- nd1value = nd1->u.node->data.intval;
- if (isUnsigned) {
- if (CInt64_LessEqualU(nd1value, nd2value))
- return 1;
- } else {
- if (CInt64_LessEqual(nd1value, nd2value))
- return 1;
- }
-
- CInt64_SetLong(&addConst, loop->induction->addConst);
- CInt64_SetLong(&neg1, -1);
- *val1 = CInt64_Sub(nd1value, nd2value);
- *val1 = CInt64_Add(*val1, addConst);
- if (IS_LINEAR_DIADIC(loop->nd18, ELESS))
- *val1 = CInt64_Add(*val1, neg1);
-
- CError_ASSERT(855, !CInt64_IsZero(&addConst));
-
- if (isUnsigned)
- *val1 = CInt64_DivU(*val1, addConst);
- else
- *val1 = CInt64_Div(*val1, addConst);
-
- if (CInt64_Equal(*val1, cint64_zero))
- return 1;
-
- if (isUnsigned) {
- if (CInt64_LessEqualU(*val1, cint64_zero))
- CError_FATAL(877);
- } else {
- if (CInt64_LessEqual(*val1, cint64_zero))
- CError_FATAL(886);
- }
-
- if (isUnsigned) {
- *val2 = CInt64_MulU(*val1, addConst);
- *val2 = CInt64_Add(*val2, nd2value);
- } else {
- *val2 = CInt64_Mul(*val1, addConst);
- *val2 = CInt64_Add(*val2, nd2value);
- }
- } else {
- return 1;
- }
-
- CInt64_SetLong(&addConst, loop->induction->addConst);
- work = CInt64_Add(nd1value, addConst);
-
- if (isUnsigned) {
- if (CInt64_LessU(work, nd1value))
- return 1;
- } else {
- if (CInt64_Less(work, nd1value))
- return 1;
- }
-
- return 0;
-}
-
-static int CheckStepOverFlow2_EmptyLoop(IROLoop *loop, CInt64 *val1, CInt64 *val2) {
- Boolean isUnsigned;
- IROLinear *nd2;
- IROLinear *nd1;
- CInt64 nd2value;
- CInt64 nd1value;
- CInt64 addConst;
- CInt64 work;
- CInt64 neg1;
-
- nd1 = loop->nd14->u.diadic.right;
- nd2 = loop->nd18->u.diadic.right;
- isUnsigned = IRO_IsUnsignedType(loop->nd18->u.diadic.right->rtype);
-
- if (IRO_IsIntConstant(nd2) && IRO_IsIntConstant(nd1)) {
- nd2value = nd2->u.node->data.intval;
- nd1value = nd1->u.node->data.intval;
- if (isUnsigned) {
- if (CInt64_LessEqualU(nd1value, nd2value))
- return 1;
- } else {
- if (CInt64_LessEqual(nd1value, nd2value))
- return 1;
- }
-
- CInt64_SetLong(&addConst, loop->induction->addConst);
- CInt64_SetLong(&neg1, -1);
- *val1 = CInt64_Sub(nd1value, nd2value);
- *val1 = CInt64_Add(*val1, addConst);
- if (IS_LINEAR_DIADIC(loop->nd18, EGREATER))
- *val1 = CInt64_Add(*val1, neg1);
-
- CError_ASSERT(995, !CInt64_IsZero(&addConst));
-
- if (isUnsigned)
- *val1 = CInt64_DivU(*val1, addConst);
- else
- *val1 = CInt64_Div(*val1, addConst);
-
- if (CInt64_Equal(*val1, cint64_zero))
- return 1;
-
- if (isUnsigned) {
- if (CInt64_LessEqualU(*val1, cint64_zero))
- return 0;
- } else {
- if (CInt64_LessEqual(*val1, cint64_zero))
- return 0;
- }
-
- if (isUnsigned) {
- *val2 = CInt64_MulU(*val1, addConst);
- *val2 = CInt64_Sub(nd1value, *val2);
- } else {
- *val2 = CInt64_Mul(*val1, addConst);
- *val2 = CInt64_Sub(nd1value, *val2);
- }
- } else {
- return 1;
- }
-
- CInt64_SetLong(&addConst, loop->induction->addConst);
- work = CInt64_Sub(nd2value, addConst);
-
- if (isUnsigned) {
- if (CInt64_GreaterU(work, nd2value))
- return 1;
- } else {
- if (CInt64_Greater(work, nd1value))
- return 1;
- }
-
- return 0;
-}
-
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