haha it's been a while since i last committed, hasn't it

1 files changed, 889 insertions, 0 deletions

diff --git a/compiler_and_linker/unsorted/LoopDetection.c b/compiler_and_linker/unsorted/LoopDetection.c
index e69de29..54bc180 100644
--- a/compiler_and_linker/unsorted/LoopDetection.c
+++ b/compiler_and_linker/unsorted/LoopDetection.c
@@ -0,0 +1,889 @@
+#include "compiler/LoopDetection.h"
+#include "compiler/CFunc.h"
+#include "compiler/PCode.h"
+#include "compiler/TOC.h"
+#include "compiler/UseDefChains.h"
+#include "compiler/CompilerTools.h"
+#include "compiler/BitVectors.h"
+#include "compiler/enode.h"
+#include "compiler/objects.h"
+
+Loop *loopsinflowgraph;
+int loopdetection_nblocks;
+static UInt32 **dominators;
+static BlockList *loopheaders;
+static int nloopheaders;
+static PCodeBlock **loopstack;
+BitVector *LoopTemp;
+void *LoopList_First;
+
+static void computedominators(void) {
+    int i;
+    PCodeBlock *block;
+    int blockCount;
+    int flag;
+    UInt32 *myvec;
+    PCLink *link;
+
+    blockCount = pcblockcount;
+    flag = 1;
+
+    dominators = oalloc(sizeof(UInt32 *) * pcblockcount);
+    for (i = 0; i < pcblockcount; i++)
+        dominators[i] = oalloc(4 * ((blockCount + 31) >> 5));
+
+    myvec = oalloc(4 * ((blockCount + 31) >> 5));
+
+    bitvectorinitialize(dominators[pcbasicblocks->blockIndex], blockCount, 0);
+    //dominators[pcbasicblocks->blockIndex][0] |= 1;
+    bitvectorsetbit(0, dominators[pcbasicblocks->blockIndex]);
+
+    for (block = pcbasicblocks->nextBlock; block; block = block->nextBlock)
+        bitvectorinitialize(dominators[block->blockIndex], blockCount, 0xFFFFFFFF);
+
+    computedepthfirstordering();
+
+    while (flag) {
+        flag = 0;
+        for (i = 0; i < pcblockcount; i++) {
+            block = depthfirstordering[i];
+            if (block && block->blockIndex != pcbasicblocks->blockIndex) {
+                bitvectorcopy(myvec, dominators[block->predecessors->block->blockIndex], blockCount);
+                for (link = block->predecessors->nextLink; link; link = link->nextLink)
+                    bitvectorintersect(myvec, dominators[link->block->blockIndex], blockCount);
+                //myvec[block->blockIndex >> 5] |= 1 << (block->blockIndex & 31);
+                bitvectorsetbit(block->blockIndex, myvec);
+
+                if (bitvectorchanged(dominators[block->blockIndex], myvec, blockCount))
+                    flag = 1;
+            }
+        }
+    }
+}
+
+static BlockList *findloopheaders(void) {
+    PCodeBlock *block;
+    PCLink *link;
+    BlockList *list;
+
+    loopheaders = NULL;
+    nloopheaders = 0;
+
+    for (block = pcbasicblocks->nextBlock; block; block = block->nextBlock) {
+        for (link = block->predecessors; link; link = link->nextLink) {
+            //if ((1 << (block->blockIndex & 31)) & dominators[link->block->blockIndex][block->blockIndex >> 5])
+            if (bitvectorgetbit(block->blockIndex, dominators[link->block->blockIndex]))
+                break;
+        }
+
+        if (link) {
+            list = oalloc(sizeof(BlockList));
+            list->block = block;
+            list->next = loopheaders;
+            loopheaders = list;
+            nloopheaders++;
+        }
+    }
+
+    return loopheaders;
+}
+
+void addblocktoloop(Loop *loop, PCodeBlock *block) {
+    BlockList *list = lalloc(sizeof(BlockList));
+
+    //loop->memberblocks[block->blockIndex >> 5] |= 1 << (block->blockIndex & 31);
+    bitvectorsetbit(block->blockIndex, loop->memberblocks);
+
+    list->block = block;
+    list->next = loop->blocks;
+    loop->blocks = list;
+}
+
+static void findnaturalloop(Loop *loop) {
+    BlockList *list;
+    BlockList *list2;
+    PCLink *link;
+    PCodeBlock *block;
+    int i;
+
+    i = 0;
+    addblocktoloop(loop, loop->body);
+    for (link = loop->body->predecessors; link; link = link->nextLink) {
+        if (bitvectorgetbit(loop->body->blockIndex, dominators[link->block->blockIndex]) && link->block != loop->body) {
+            addblocktoloop(loop, link->block);
+            loopstack[i++] = link->block;
+        }
+    }
+
+    while (i) {
+        link = loopstack[--i]->predecessors;
+        while (link) {
+            if (!bitvectorgetbit(link->block->blockIndex, loop->memberblocks)) {
+                addblocktoloop(loop, link->block);
+                loopstack[i++] = link->block;
+            }
+            link = link->nextLink;
+        }
+    }
+
+    for (list = loop->blocks; list; list = list->next) {
+        block = list->block;
+        for (link = block->successors; link; link = link->nextLink) {
+            if (!bitvectorgetbit(link->block->blockIndex, loop->memberblocks)) {
+                bitvectorsetbit(block->blockIndex, loop->vec24);
+                break;
+            }
+        }
+    }
+
+    for (list = loop->blocks; list; list = list->next) {
+        for (list2 = loop->blocks; list2; list2 = list2->next) {
+            if (bitvectorgetbit(list2->block->blockIndex, loop->vec24) &&
+                !bitvectorgetbit(list->block->blockIndex, dominators[list2->block->blockIndex]))
+                break;
+        }
+
+        if (!list2)
+            bitvectorsetbit(list->block->blockIndex, loop->vec28);
+    }
+
+    for (list = loop->blocks; list; list = list->next) {
+        for (link = loop->body->predecessors; link; link = link->nextLink) {
+            if (bitvectorgetbit(link->block->blockIndex, loop->memberblocks) &&
+                !bitvectorgetbit(list->block->blockIndex, dominators[link->block->blockIndex]))
+                break;
+        }
+
+        if (!link)
+            bitvectorsetbit(list->block->blockIndex, loop->vec2C);
+    }
+}
+
+static void addlooptolist(Loop *loop, Loop **list) {
+    Loop **scan;
+    Loop *scanloop;
+
+    scan = list;
+    while ((scanloop = *scan)) {
+        if (bitvectorgetbit(loop->body->blockIndex, scanloop->memberblocks)) {
+            loop->parent = scanloop;
+            addlooptolist(loop, &scanloop->children);
+            return;
+        }
+
+        if (bitvectorgetbit(scanloop->body->blockIndex, loop->memberblocks)) {
+            *scan = scanloop->nextSibling;
+            scanloop->parent = loop;
+            scanloop->nextSibling = loop->children;
+            loop->children = scanloop;
+        } else {
+            scan = &scanloop->nextSibling;
+        }
+    }
+
+    loop->nextSibling = *list;
+    *list = loop;
+}
+
+static void findnaturalloops(void) {
+    Loop *loop;
+    int size;
+
+    loopdetection_nblocks = pcblockcount + 5 * nloopheaders;
+    loopstack = oalloc(sizeof(PCodeBlock *) * pcblockcount);
+    while (loopheaders) {
+        loop = lalloc(sizeof(Loop));
+        loop->parent = loop->nextSibling = loop->children = NULL;
+        loop->body = loopheaders->block;
+        loop->preheader = NULL;
+        loop->blocks = NULL;
+        loop->basicInductionVars = NULL;
+        loop->footer = NULL;
+        loop->pc18 = NULL;
+        loop->loopWeight = loop->body->loopWeight;
+
+        bitvectorinitialize(loop->memberblocks = lalloc(4 * ((loopdetection_nblocks + 31) >> 5)), loopdetection_nblocks, 0);
+        bitvectorinitialize(loop->vec24 = lalloc(4 * ((loopdetection_nblocks + 31) >> 5)), loopdetection_nblocks, 0);
+        bitvectorinitialize(loop->vec28 = lalloc(4 * ((loopdetection_nblocks + 31) >> 5)), loopdetection_nblocks, 0);
+        bitvectorinitialize(loop->vec2C = lalloc(4 * ((loopdetection_nblocks + 31) >> 5)), loopdetection_nblocks, 0);
+
+        findnaturalloop(loop);
+        addlooptolist(loop, &loopsinflowgraph);
+
+        loopheaders = loopheaders->next;
+    }
+}
+
+static PCodeBlock *makepreheaderblock(void) {
+    PCodeLabel *label;
+    PCodeBlock *block;
+
+    label = makepclabel();
+    block = lalloc(sizeof(PCodeBlock));
+    block->nextBlock = NULL;
+    block->prevBlock = NULL;
+    block->labels = NULL;
+    block->successors = NULL;
+    block->predecessors = NULL;
+    block->firstPCode = block->lastPCode = NULL;
+    block->pcodeCount = 0;
+    block->flags = 0;
+    block->blockIndex = pcblockcount++;
+    pclabel(block, label);
+    return block;
+}
+
+static void insertpreheaderbefore(PCodeBlock *a, PCodeBlock *b) {
+    a->nextBlock = b;
+    a->prevBlock = b->prevBlock;
+    b->prevBlock->nextBlock = a;
+    b->prevBlock = a;
+}
+
+void insertpreheaderblock(Loop *loop) {
+    PCodeBlock *preheader;
+    PCodeBlock *block29;
+    PCodeBlock *block28;
+    PCode *pcode27;
+    PCLink *link; // r26
+    PCLink **linkptr; // r25
+    PCodeLabel *newlabel; // r23
+    PCLink *innerlink;
+    PCodeBlock *block;
+    PCodeArg *arg;
+    int i;
+
+    preheader = loop->preheader = makepreheaderblock();
+    block29 = NULL;
+    block28 = loop->body;
+
+    if (!block28->labels)
+        pclabel(block28, makepclabel());
+
+    appendpcode(preheader, makepcode(PC_B, block28->labels));
+    preheader->loopWeight = loop->parent ? loop->parent->loopWeight : 1;
+
+    linkptr = &block28->predecessors;
+    while ((link = *linkptr)) {
+        if (bitvectorgetbit(link->block->blockIndex, loop->memberblocks)) {
+            linkptr = &link->nextLink;
+        } else {
+            if (link->block->pcodeCount) {
+                pcode27 = link->block->lastPCode;
+                if (pcode27->op == PC_B) {
+#line 462
+                    CError_ASSERT(pcode27->args[0].kind == PCOp_LABEL);
+                    if (pcode27->args[0].data.label.label->block == block28)
+                        pcode27->args[0].data.label.label = preheader->labels;
+                } else if (pcode27->op == PC_BT || pcode27->op == PC_BF) {
+#line 474
+                    CError_ASSERT(pcode27->args[2].kind == PCOp_LABEL);
+                    if (pcode27->args[2].data.label.label->block == block28)
+                        pcode27->args[2].data.label.label = preheader->labels;
+                } else if (pcode27->op == PC_BCTR) {
+                    if (pcode27->argCount > 1 && pcode27->args[1].kind == PCOp_MEMORY) {
+                        Object *obj = pcode27->args[1].data.mem.obj;
+                        PCodeLabel **array = (PCodeLabel **) obj->u.data.u.switchtable.data;
+                        int i;
+                        for (i = 0; i < obj->u.data.u.switchtable.size; i++) {
+                            if (array[i]->block == block28)
+                                array[i] = preheader->labels;
+                        }
+                    } else {
+                        CodeLabelList *cll;
+                        for (cll = codelabellist; cll; cll = cll->next) {
+                            if (cll->label->pclabel->block == block28)
+                                cll->label->pclabel = preheader->labels;
+                        }
+                    }
+                } else {
+#line 505
+                    CError_ASSERT(link->block->nextBlock == block28);
+                }
+            }
+
+            for (innerlink = link->block->successors; innerlink; innerlink = innerlink->nextLink) {
+                if (innerlink->block == block28)
+                    innerlink->block = preheader;
+            }
+
+            *linkptr = link->nextLink;;
+            link->nextLink = preheader->predecessors;
+            preheader->predecessors = link;
+        }
+    }
+
+    if (!bitvectorgetbit(block28->prevBlock->blockIndex, loop->memberblocks)) {
+        insertpreheaderbefore(preheader, block28);
+
+        if (
+            (!block28->nextBlock || !bitvectorgetbit(block28->nextBlock->blockIndex, loop->memberblocks)) &&
+            block28->lastPCode &&
+            (block28->lastPCode->flags & fPCodeFlag1) &&
+            block28->lastPCode->op != PC_BDNZ
+            ) {
+            i = block28->lastPCode->argCount;
+            arg = block28->lastPCode->args;
+            while (i && arg->kind != PCOp_LABEL) {
+                arg++;
+                i--;
+            }
+
+            if (i && arg->kind == PCOp_LABEL && arg->data.label.label->block == block28) {
+                block29 = makepreheaderblock();
+                insertpreheaderbefore(block29, block28);
+                newlabel = makepclabel();
+                pclabel(block29, newlabel);
+                arg->data.label.label = newlabel;
+
+                link = lalloc(sizeof(PCLink));
+                link->block = block28;
+                link->nextLink = block29->predecessors;
+                block29->predecessors = link;
+
+                link = lalloc(sizeof(PCLink));
+                link->block = block28;
+                link->nextLink = block29->successors;
+                block29->successors = link;
+
+                for (link = block28->successors; link; link = link->nextLink) {
+                    if (link->block == block28)
+                        link->block = block29;
+                }
+                for (link = block28->predecessors; link; link = link->nextLink) {
+                    if (link->block == block28)
+                        link->block = block29;
+                }
+
+                bitvectorsetbit(block29->blockIndex, loop->vec2C);
+                addblocktoloop(loop, block29);
+            }
+        }
+    } else {
+        for (block = pcbasicblocks; block; block = block->nextBlock) {
+            if (bitvectorgetbit(block->blockIndex, loop->memberblocks))
+                break;
+        }
+        insertpreheaderbefore(preheader, block);
+    }
+
+    link = lalloc(sizeof(PCLink));
+    link->block = preheader;
+    link->nextLink = block28->predecessors;
+    block28->predecessors = link;
+
+    link = lalloc(sizeof(PCLink));
+    link->block = block28;
+    link->nextLink = preheader->successors;
+    preheader->successors = link;
+
+    for (loop = loop->parent; loop; loop = loop->parent) {
+        addblocktoloop(loop, preheader);
+        if (bitvectorgetbit(block28->blockIndex, loop->vec28)) {
+            bitvectorsetbit(preheader->blockIndex, loop->vec28);
+            if (block29)
+                bitvectorsetbit(block29->blockIndex, loop->vec28);
+        }
+        if (bitvectorgetbit(block28->blockIndex, loop->vec2C)) {
+            bitvectorsetbit(preheader->blockIndex, loop->vec2C);
+            if (block29)
+                bitvectorsetbit(block29->blockIndex, loop->vec2C);
+        }
+    }
+}
+
+static void insertpreheaderblocks(Loop *loop) {
+    while (loop) {
+        if (loop->children)
+            insertpreheaderblocks(loop->children);
+        insertpreheaderblock(loop);
+        loop = loop->nextSibling;
+    }
+}
+
+void findloopsinflowgraph(void) {
+    loopsinflowgraph = NULL;
+    computedominators();
+    if (findloopheaders()) {
+        findnaturalloops();
+        insertpreheaderblocks(loopsinflowgraph);
+    }
+    freeoheap();
+}
+
+static int checklooplimits(SInt32 opcode, SInt32 condition, SInt32 c, SInt32 d, SInt32 addend, SInt32 *result) {
+    if (opcode == PC_BT) {
+        if (condition == 0) {
+            if (addend <= 0)
+                return 0;
+            if (c < d)
+                *result = (d - c + addend - 1) / addend;
+            else
+                *result = 0;
+        } else if (condition == 1) {
+            if (addend >= 0)
+                return 0;
+            if (c > d)
+                *result = (c - d - addend - 1) / -addend;
+            else
+                *result = 0;
+        } else {
+            return 0;
+        }
+    } else {
+        if (condition == 0) {
+            if (addend >= 0)
+                return 0;
+            if (c >= d)
+                *result = (c - d - addend) / -addend;
+            else
+                *result = 0;
+        } else if (condition == 1) {
+            if (addend <= 0)
+                return 0;
+            if (c <= d)
+                *result = (d - c + addend) / addend;
+            else
+                *result = 0;
+        } else if (c < d) {
+            if (addend <= 0)
+                return 0;
+            if ((d - c) % addend)
+                return 0;
+            *result = (d - c) / addend;
+        } else if (c > d) {
+            if (addend >= 0)
+                return 0;
+            if ((c - d) % -addend)
+                return 0;
+            *result = (c - d) / -addend;
+        } else {
+            *result = 0;
+        }
+    }
+
+    return 1;
+}
+
+static int checkunsignedlooplimits(SInt32 opcode, SInt32 condition, UInt32 c, UInt32 d, SInt32 addend, UInt32 *result) {
+    if (opcode == PC_BT) {
+        if (condition == 0) {
+            if (addend <= 0)
+                return 0;
+            if (c < d)
+                *result = (d - c + addend - 1) / addend;
+            else
+                *result = 0;
+        } else if (condition == 1) {
+            if (addend >= 0)
+                return 0;
+            if (c > d)
+                *result = (c - d - addend - 1) / -addend;
+            else
+                *result = 0;
+        } else {
+            return 0;
+        }
+    } else {
+        if (condition == 0) {
+            if (addend >= 0)
+                return 0;
+            if (c >= d)
+                *result = (c - d - addend) / -addend;
+            else
+                *result = 0;
+        } else if (condition == 1) {
+            if (addend <= 0)
+                return 0;
+            if (c <= d)
+                *result = (d - c + addend) / addend;
+            else
+                *result = 0;
+        } else if (c < d) {
+            if (addend <= 0)
+                return 0;
+            if ((d - c) % addend)
+                return 0;
+            *result = (d - c) / addend;
+        } else if (c > d) {
+            if (addend >= 0)
+                return 0;
+            if ((c - d) % -addend)
+                return 0;
+            *result = (c - d) / -addend;
+        } else {
+            *result = 0;
+        }
+    }
+
+    return (*result & 0x80000000) == 0;
+}
+
+static int checkunknownloop(int a, int b, int c, unsigned char *op) {
+    if (a == PC_BT) {
+        if (b == 0) {
+            if (c <= 0)
+                return 0;
+            *op = ELESS;
+        } else if (b == 1) {
+            if (c >= 0)
+                return 0;
+            *op = EGREATER;
+        } else {
+            return 0;
+        }
+    } else {
+        if (b == 0) {
+            if (c >= 0)
+                return 0;
+            *op = EGREATEREQU;
+        } else if (b == 1) {
+            if (c <= 0)
+                return 0;
+            *op = ELESSEQU;
+        } else if (c == 1) {
+            *op = ENOTEQU;
+        } else if (c == -1) {
+            *op = ENOTEQU;
+        } else {
+            return 0;
+        }
+    }
+
+    return 1;
+}
+
+static void checkcountingloop(Loop *loop) {
+    RegUseOrDef *list;
+    PCode *lastpcode;
+    PCode *prevpcode;
+    PCode *pc8;
+    PCode *check;
+    short op12;
+    short reg11;
+    SInt16 reg4;
+    short reg11b;
+    Loop *child;
+
+    if (!(lastpcode = loop->body->lastPCode))
+        return;
+    if (lastpcode->op != PC_BT && lastpcode->op != PC_BF)
+        return;
+    if (lastpcode->args[2].kind != PCOp_LABEL)
+        return;
+
+    if (!bitvectorgetbit(lastpcode->args[2].data.label.label->block->blockIndex, loop->memberblocks))
+        return;
+    if (bitvectorgetbit(loop->body->nextBlock->blockIndex, loop->memberblocks))
+        return;
+
+    reg11 = lastpcode->args[0].data.reg.reg;
+    reg4 = lastpcode->args[1].data.imm.value;
+    prevpcode = lastpcode->prevPCode;
+    if (!prevpcode)
+        return;
+
+    op12 = prevpcode->op;
+    if (op12 == PC_ADDI && prevpcode->args[2].kind == PCOp_IMMEDIATE) {
+        pc8 = prevpcode;
+        prevpcode = prevpcode->prevPCode;
+        if (!prevpcode)
+            return;
+
+        op12 = prevpcode->op;
+        if (pc8->args[0].data.reg.reg != pc8->args[1].data.reg.reg)
+            return;
+        if (op12 != PC_CMP && op12 != PC_CMPL && op12 != PC_CMPI && op12 != PC_CMPLI)
+            return;
+        if (prevpcode->args[1].data.reg.reg == pc8->args[0].data.reg.reg)
+            return;
+        if ((loop->step = pc8->args[2].data.imm.value) == 0)
+            return;
+    }
+
+    if (op12 != PC_CMP && op12 != PC_CMPL && op12 != PC_CMPI && op12 != PC_CMPLI)
+        return;
+
+    if (prevpcode->args[0].data.reg.reg != reg11)
+        return;
+
+    reg11b = prevpcode->args[1].data.reg.reg;
+    if (reg11b < 32)
+        return;
+
+    if (loop->preheader->nextBlock != lastpcode->args[2].data.label.label->block)
+        return;
+
+    if (op12 == PC_CMPI) {
+        if (prevpcode->prevPCode)
+            return;
+        loop->upper = prevpcode->args[2].data.imm.value;
+        loop->upperType = LOOP_BOUND_CONSTANT;
+    } else if (op12 == PC_CMPLI) {
+        if (prevpcode->prevPCode)
+            return;
+        loop->upper = prevpcode->args[2].data.imm.value & 0xFFFF;
+        loop->upperType = LOOP_BOUND_CONSTANT;
+    } else if (op12 == PC_CMP || op12 == PC_CMPL) {
+        if (prevpcode->prevPCode) {
+            if (
+                prevpcode->prevPCode->op == PC_LI &&
+                prevpcode->prevPCode->args[1].kind == PCOp_IMMEDIATE &&
+                prevpcode->prevPCode->args[0].data.reg.reg == prevpcode->args[2].data.reg.reg &&
+                !prevpcode->prevPCode->prevPCode
+                ) {
+                loop->upper = prevpcode->prevPCode->args[1].data.imm.value;
+                loop->upperType = LOOP_BOUND_CONSTANT;
+            } else if (
+                prevpcode->prevPCode->op == PC_LIS &&
+                prevpcode->prevPCode->args[1].kind == PCOp_IMMEDIATE &&
+                prevpcode->prevPCode->args[0].data.reg.reg == prevpcode->args[2].data.reg.reg &&
+                !prevpcode->prevPCode->prevPCode
+                ) {
+                loop->upper = prevpcode->prevPCode->args[1].data.imm.value << 16;
+                loop->upperType = LOOP_BOUND_CONSTANT;
+            } else if (
+                prevpcode->prevPCode->op == PC_ADDI &&
+                prevpcode->prevPCode->args[2].kind == PCOp_IMMEDIATE &&
+                prevpcode->prevPCode->args[0].data.reg.reg == prevpcode->args[2].data.reg.reg &&
+                prevpcode->prevPCode->args[1].data.reg.reg == prevpcode->args[2].data.reg.reg &&
+                prevpcode->prevPCode->prevPCode &&
+                prevpcode->prevPCode->prevPCode->op == PC_LIS &&
+                prevpcode->prevPCode->prevPCode->args[1].kind == PCOp_IMMEDIATE &&
+                prevpcode->prevPCode->prevPCode->args[0].data.reg.reg == prevpcode->args[2].data.reg.reg &&
+                !prevpcode->prevPCode->prevPCode->prevPCode
+                ) {
+                loop->upper = prevpcode->prevPCode->args[2].data.imm.value +
+                              (prevpcode->prevPCode->prevPCode->args[1].data.imm.value << 16);
+                loop->upperType = LOOP_BOUND_CONSTANT;
+            } else {
+                return;
+            }
+        } else {
+            pc8 = NULL;
+            for (list = reg_Defs[RegClass_GPR][prevpcode->args[2].data.reg.reg]; list; list = list->next) {
+                if (bitvectorgetbit(Defs[list->id].pcode->block->blockIndex, loop->memberblocks))
+                    return;
+            }
+            for (list = reg_Defs[RegClass_GPR][prevpcode->args[2].data.reg.reg]; list; list = list->next) {
+                if (bitvectorgetbit(list->id, usedefinfo[loop->preheader->blockIndex].defvec8)) {
+                    if (!pc8) {
+                        pc8 = Defs[list->id].pcode;
+                        if (
+                            pc8->op == PC_LI &&
+                            pc8->args[1].kind == PCOp_IMMEDIATE
+                            ) {
+                            loop->upper = pc8->args[1].data.imm.value;
+                            loop->upperType = LOOP_BOUND_CONSTANT;
+                        } else if (
+                            pc8->op == PC_LIS &&
+                            pc8->args[1].kind == PCOp_IMMEDIATE
+                            ) {
+                            loop->upper = pc8->args[1].data.imm.value << 16;
+                            loop->upperType = LOOP_BOUND_CONSTANT;
+                        } else if (
+                            pc8->op == PC_ADDI &&
+                            pc8->args[2].kind == PCOp_IMMEDIATE &&
+                            pc8->args[1].data.reg.reg == prevpcode->args[2].data.reg.reg &&
+                            pc8->prevPCode &&
+                            pc8->prevPCode->op == PC_LIS &&
+                            pc8->prevPCode->args[1].kind == PCOp_IMMEDIATE &&
+                            pc8->prevPCode->args[0].data.reg.reg == prevpcode->args[2].data.reg.reg
+                            ) {
+                            loop->upper = pc8->args[2].data.imm.value +
+                                          (pc8->prevPCode->args[1].data.imm.value << 16);
+                            loop->upperType = LOOP_BOUND_CONSTANT;
+                        } else {
+                            loop->upperType = LOOP_BOUND_VARIABLE;
+                            break;
+                        }
+                    } else {
+                        loop->upperType = LOOP_BOUND_VARIABLE;
+                        break;
+                    }
+                }
+            }
+
+            if (loop->upperType == LOOP_BOUND_INDETERMINATE)
+                loop->upperType = LOOP_BOUND_VARIABLE;
+        }
+    }
+
+    pc8 = NULL;
+
+    for (list = reg_Defs[RegClass_GPR][reg11b]; list; list = list->next) {
+        check = Defs[list->id].pcode;
+        if (bitvectorgetbit(check->block->blockIndex, loop->memberblocks)) {
+            if (!pc8) {
+                pc8 = check;
+                if (check->op != PC_ADDI)
+                    return;
+                if (check->args[1].data.reg.reg != reg11b)
+                    return;
+                if (check->args[2].kind != PCOp_IMMEDIATE)
+                    return;
+                if ((loop->step = check->args[2].data.imm.value) == 0)
+                    return;
+            } else {
+                return;
+            }
+        }
+    }
+
+    if (!pc8)
+        return;
+
+    if (pc8->block != prevpcode->block && !bitvectorgetbit(prevpcode->block->blockIndex, loop->vec2C))
+        return;
+
+    if (loop->children) {
+        for (child = loop->children; child; child = child->nextSibling) {
+            if (bitvectorgetbit(pc8->block->blockIndex, child->memberblocks))
+                return;
+        }
+    }
+
+    loop->pc18 = pc8;
+
+    pc8 = NULL;
+
+    for (list = reg_Defs[RegClass_GPR][reg11b]; list; list = list->next) {
+        if (bitvectorgetbit(list->id, usedefinfo[loop->preheader->blockIndex].defvec8)) {
+            if (!pc8) {
+                pc8 = Defs[list->id].pcode;
+                if (
+                    pc8->op == PC_LI &&
+                    pc8->args[1].kind == PCOp_IMMEDIATE
+                    ) {
+                    loop->lower = pc8->args[1].data.imm.value;
+                    loop->lowerType = LOOP_BOUND_CONSTANT;
+                } else if (
+                    pc8->op == PC_LIS &&
+                    pc8->args[1].kind == PCOp_IMMEDIATE
+                    ) {
+                    loop->lower = pc8->args[1].data.imm.value << 16;
+                    loop->lowerType = LOOP_BOUND_CONSTANT;
+                } else if (
+                    pc8->op == PC_ADDI &&
+                    pc8->args[2].kind == PCOp_IMMEDIATE &&
+                    pc8->args[1].data.reg.reg == reg11b &&
+                    pc8->prevPCode &&
+                    pc8->prevPCode->op == PC_LIS &&
+                    pc8->prevPCode->args[1].kind == PCOp_IMMEDIATE &&
+                    pc8->prevPCode->args[0].data.reg.reg == reg11b
+                    ) {
+                    loop->lower = pc8->args[2].data.imm.value +
+                                  (pc8->prevPCode->args[1].data.imm.value << 16);
+                    loop->lowerType = LOOP_BOUND_CONSTANT;
+                } else {
+                    loop->lowerType = LOOP_BOUND_VARIABLE;
+                    break;
+                }
+            } else {
+                loop->lowerType = LOOP_BOUND_INDETERMINATE;
+                break;
+            }
+        }
+    }
+
+    if (loop->lowerType == LOOP_BOUND_INDETERMINATE)
+        loop->lowerType = LOOP_BOUND_VARIABLE;
+
+    if (loop->lowerType == LOOP_BOUND_CONSTANT && loop->upperType == LOOP_BOUND_CONSTANT) {
+        if (op12 == PC_CMP || op12 == PC_CMPI) {
+            if (!checklooplimits(lastpcode->op, reg4, loop->lower, loop->upper, loop->step, &loop->iterationCount))
+                return;
+        } else {
+            if (!checkunsignedlooplimits(lastpcode->op, reg4, loop->lower, loop->upper, loop->step, (UInt32 *) &loop->iterationCount))
+                return;
+        }
+        loop->isKnownCountingLoop = 1;
+    } else if (loop->lowerType != LOOP_BOUND_INDETERMINATE || loop->upperType != LOOP_BOUND_INDETERMINATE) {
+        if (!checkunknownloop(lastpcode->op, reg4, loop->step, &loop->unknownCondition))
+            return;
+        loop->isUnknownCountingLoop = 1;
+    }
+}
+
+void analyzeForCountableLoops(Loop *loop) {
+    if (!loop)
+        return;
+
+    while (loop) {
+        if (loop->children)
+            analyzeForCountableLoops(loop->children);
+        checkcountingloop(loop);
+        loop = loop->nextSibling;
+    }
+}
+
+void analyzeloop(Loop *loop) {
+    BlockList *list;
+    PCodeBlock *block;
+    PCode *pcode;
+
+    loop->bodySize = 0;
+    loop->x4D = 0;
+    loop->x4E = 0;
+    loop->x4F = 1;
+    loop->isKnownCountingLoop = 0;
+    loop->isUnknownCountingLoop = 0;
+    loop->lowerType = LOOP_BOUND_INDETERMINATE;
+    loop->upperType = LOOP_BOUND_INDETERMINATE;
+    loop->iterationCount = -1;
+    loop->x57 = 0;
+    loop->x52 = 0;
+
+    for (list = loop->blocks; list; list = list->next) {
+        block = list->block;
+        if (!loop->children)
+            block->flags |= fPCBlockFlag2000;
+        loop->bodySize += block->pcodeCount;
+
+        if (block != loop->body) {
+            if (!block->successors || !block->predecessors || block->successors->nextLink || block->predecessors->nextLink)
+                loop->x4F = 0;
+        }
+
+        if ((block->flags & fPCBlockFlag4000) == fPCBlockFlag4000)
+            loop->x52 = 1;
+
+        for (pcode = block->firstPCode; pcode; pcode = pcode->nextPCode) {
+            if (PCODE_FLAG_SET_T(pcode) & fLink)
+                loop->x4D = 1;
+
+            if (pcode->op == PC_BCTRL || pcode->op == PC_BCTR || pcode->op == PC_BCCTR || pcode->op == PC_MTCTR || pcode->op == PC_MFCTR) {
+                loop->x4E = 1;
+            } else if (pcode->flags & fPCodeFlag2) {
+                if (pcode->op == PC_LBZX || pcode->op == PC_LHZX || pcode->op == PC_LHAX || pcode->op == PC_LWZX || pcode->op == PC_LFSX || pcode->op == PC_LFDX)
+                    loop->x53 = 1;
+            } else if (pcode->flags & fPCodeFlag4) {
+                if (pcode->op == PC_STBX || pcode->op == PC_STHX || pcode->op == PC_STWX || pcode->op == PC_STFSX || pcode->op == PC_STFDX)
+                    loop->x54 = 1;
+            } else {
+                if (pcode->op == PC_EIEIO || pcode->op == PC_SYNC || pcode->op == PC_ISYNC)
+                    loop->x57 = 1;
+            }
+        }
+    }
+
+    if (!loop->children && !loop->x4D && loop->bodySize < 32) {
+        for (list = loop->blocks; list; list = list->next)
+            list->block->flags |= fPCBlockFlag2000;
+    }
+}
+
+static void analyzeloops(Loop *loop) {
+    while (loop) {
+        if (loop->children)
+            analyzeloops(loop->children);
+        analyzeloop(loop);
+        loop = loop->nextSibling;
+    }
+}
+
+void analyzeloopsinflowgraph(void) {
+    if (loopsinflowgraph)
+        analyzeloops(loopsinflowgraph);
+}
+