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MWCC/compiler_and_linker/BackEnd/PowerPC/CodeGenerator/Switch.c

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#include "compiler/Switch.h"
#include "compiler/CError.h"
#include "compiler/CFunc.h"
#include "compiler/CInt64.h"
#include "compiler/CParser.h"
#include "compiler/InstrSelection.h"
#include "compiler/ObjGenMachO.h"
#include "compiler/Operands.h"
#include "compiler/PCode.h"
#include "compiler/PCodeUtilities.h"
#include "compiler/RegisterInfo.h"
#include "compiler/TOC.h"
#include "compiler/CompilerTools.h"
#include "compiler/objects.h"
ObjectList *switchtables;
static SwitchCase **caselabels;
static CaseRange *caseranges;
static SInt32 ncases;
static SInt32 nranges_minus1;
static CInt64 min;
static CInt64 max;
static CInt64 first;
static short selector_gpr;
static short selector_gprHi;
static Type *selector_type;
static PCodeLabel *defaultlabel;
static CInt64 range;
static int compare_cases(const void *a, const void *b) {
const SwitchCase **casea = (const SwitchCase **) a;
const SwitchCase **caseb = (const SwitchCase **) b;
if (CInt64_Less((*casea)->min, (*caseb)->min))
return -1;
if (CInt64_Greater((*casea)->min, (*caseb)->min))
return 1;
return 0;
}
static void build_case_ranges(Type *type, SwitchCase *cases, CLabel *label) {
SwitchCase **caseptr;
SInt32 i;
SwitchCase *curcase;
CaseRange *currange;
if (type->size == 8) {
min.lo = 0;
min.hi = 0x80000000;
max.lo = 0xFFFFFFFF;
max.hi = 0x7FFFFFFF;
} else if (type->size == 4) {
CInt64_SetLong(&min, 0x80000000);
CInt64_SetLong(&max, 0x7FFFFFFF);
} else if (is_unsigned(type)) {
min.hi = 0;
min.lo = 0;
max.hi = 0;
max.lo = 0xFFFF;
} else {
CInt64_SetLong(&min, -0x8000);
CInt64_SetLong(&max, 0x7FFF);
}
caselabels = lalloc(sizeof(SwitchCase *) * ncases);
caseptr = caselabels;
while (cases) {
*caseptr = cases;
cases = cases->next;
++caseptr;
}
caseranges = lalloc(((ncases * 2) + 2) * sizeof(CaseRange));
if (type->size < 8) {
for (i = 0; i < ncases; i++)
CInt64_SetLong(&caselabels[i]->min, caselabels[i]->min.lo);
}
qsort(caselabels, ncases, sizeof(SwitchCase *), &compare_cases);
currange = caseranges;
currange->min = min;
currange->range = CInt64_Sub(max, min);
currange->label = label->pclabel;
for (i = 0; i < ncases; i++) {
curcase = caselabels[i];
if (CInt64_GreaterEqual(curcase->min, min) && CInt64_LessEqual(curcase->min, max)) {
if (CInt64_Equal(currange->min, min))
first = curcase->min;
range = CInt64_Sub(curcase->min, first);
if (CInt64_Greater(curcase->min, currange->min)) {
currange->range = CInt64_Sub(CInt64_Sub(curcase->min, currange->min), cint64_one);
(++currange)->min = curcase->min;
} else if (CInt64_Greater(currange->min, min) && curcase->label->pclabel == currange[-1].label) {
currange[-1].range = CInt64_Add(currange[-1].range, cint64_one);
if (CInt64_Equal(currange->range, cint64_zero)) {
currange--;
} else {
currange->min = CInt64_Add(currange->min, cint64_one);
currange->range = CInt64_Sub(currange->range, cint64_one);
}
continue;
}
currange->range = cint64_zero;
currange->label = curcase->label->pclabel;
if (CInt64_Less(curcase->min, max)) {
currange++;
currange->min = CInt64_Add(curcase->min, cint64_one);
currange->range = CInt64_Sub(max, currange->min);
currange->label = label->pclabel;
}
}
}
nranges_minus1 = currange - caseranges;
}
static void treecompare(SInt32 start, SInt32 end) {
SInt32 r30;
SInt32 r29;
CaseRange *currange;
int count;
count = end - start;
CError_ASSERT(175, selector_type->size <= 4);
r29 = start + (count >> 1) + 1;
currange = caseranges + r29;
if (CInt64_Equal(currange[-1].range, cint64_zero) && (!(count & 1) || (CInt64_NotEqual(currange->range, cint64_zero) && count > 1))) {
currange--;
r29--;
}
r30 = r29 - 1;
if (selector_type->size < 4 && is_unsigned(selector_type)) {
emitpcode(PC_CMPLI, 0, selector_gpr, CInt64_GetULong(&currange->min));
} else if (FITS_IN_SHORT((SInt32) CInt64_GetULong(&currange->min))) {
emitpcode(PC_CMPI, 0, selector_gpr, CInt64_GetULong(&currange->min));
} else {
SInt32 value = CInt64_GetULong(&currange->min);
int reg = ALLOC_GPR();
load_immediate(reg, value);
emitpcode(PC_CMP, 0, selector_gpr, reg);
}
if (CInt64_Equal(currange->range, cint64_zero) && r29 < end) {
branch_conditional(0, EEQU, 1, currange->label);
r29++;
}
if (r29 == end) {
if (start == r30) {
if (caseranges[start].label == caseranges[end].label) {
branch_always(caseranges[start].label);
} else {
branch_conditional(0, EGREATEREQU, 1, caseranges[end].label);
branch_always(caseranges[start].label);
}
} else {
branch_conditional(0, EGREATEREQU, 1, caseranges[end].label);
treecompare(start, r30);
}
} else {
if (start == r30) {
branch_conditional(0, ELESS, 1, caseranges[start].label);
treecompare(r29, end);
} else {
PCodeLabel *label = makepclabel();
branch_conditional(0, EGREATEREQU, 1, label);
treecompare(start, r30);
branch_label(label);
treecompare(r29, end);
}
}
}
static void I8_treecompare(SInt32 start, SInt32 end) {
SInt32 r30;
SInt32 r29;
CaseRange *currange;
int count;
count = end - start;
r29 = start + (count >> 1) + 1;
currange = caseranges + r29;
if (CInt64_Equal(currange[-1].range, cint64_zero) && (!(count & 1) || (CInt64_NotEqual(currange->range, cint64_zero) && count > 1))) {
currange--;
r29--;
}
r30 = r29 - 1;
if (CInt64_Equal(currange->range, cint64_zero) && r29 < end) {
short a = ALLOC_GPR();
short b = ALLOC_GPR();
load_immediate(a, currange->min.lo);
load_immediate(b, currange->min.hi);
emitpcode(PC_XOR, a, selector_gpr, a);
emitpcode(PC_XOR, b, selector_gprHi, b);
emitpcode(PC_OR, b, a, b);
emitpcode(PC_CMPI, 0, b, 0);
branch_conditional(0, EEQU, 1, currange->label);
r29++;
}
if (r29 == end) {
if (start == r30) {
if (caseranges[start].label == caseranges[end].label) {
branch_always(caseranges[start].label);
} else {
short a = ALLOC_GPR();
short b = ALLOC_GPR();
short c = ALLOC_GPR();
short d = ALLOC_GPR();
load_immediate(a, currange->min.lo);
load_immediate(b, currange->min.hi);
if (TYPE_INTEGRAL(selector_type)->integral != IT_ULONGLONG && TYPE_INTEGRAL(selector_type)->integral != IT_ULONGLONG) {
emitpcode(PC_XORIS, c, selector_gprHi, 0x8000);
emitpcode(PC_XORIS, d, b, 0x8000);
} else {
c = selector_gprHi;
d = b;
}
emitpcode(PC_SUBFC, a, a, selector_gpr);
emitpcode(PC_SUBFE, b, d, c);
emitpcode(PC_SUBFE, b, a, a);
emitpcode(PC_NEG, b, b);
emitpcode(PC_CMPI, 0, b, 0);
branch_conditional(0, EEQU, 1, caseranges[end].label);
branch_always(caseranges[start].label);
}
} else {
short a = ALLOC_GPR();
short b = ALLOC_GPR();
short c = ALLOC_GPR();
short d = ALLOC_GPR();
load_immediate(a, currange->min.lo);
load_immediate(b, currange->min.hi);
if (TYPE_INTEGRAL(selector_type)->integral != IT_ULONGLONG && TYPE_INTEGRAL(selector_type)->integral != IT_ULONGLONG) {
emitpcode(PC_XORIS, c, selector_gprHi, 0x8000);
emitpcode(PC_XORIS, d, b, 0x8000);
} else {
c = selector_gprHi;
d = b;
}
emitpcode(PC_SUBFC, a, a, selector_gpr);
emitpcode(PC_SUBFE, b, d, c);
emitpcode(PC_SUBFE, b, a, a);
emitpcode(PC_NEG, b, b);
emitpcode(PC_CMPI, 0, b, 0);
branch_conditional(0, EEQU, 1, caseranges[end].label);
I8_treecompare(start, r30);
}
} else {
if (start == r30) {
short a = ALLOC_GPR();
short b = ALLOC_GPR();
short c = ALLOC_GPR();
short d = ALLOC_GPR();
load_immediate(a, currange->min.lo);
load_immediate(b, currange->min.hi);
if (TYPE_INTEGRAL(selector_type)->integral != IT_ULONGLONG && TYPE_INTEGRAL(selector_type)->integral != IT_ULONGLONG) {
emitpcode(PC_XORIS, c, selector_gprHi, 0x8000);
emitpcode(PC_XORIS, d, b, 0x8000);
} else {
c = selector_gprHi;
d = b;
}
emitpcode(PC_SUBFC, a, selector_gpr, a);
emitpcode(PC_SUBFE, b, c, d);
emitpcode(PC_SUBFE, b, a, a);
emitpcode(PC_NEG, b, b);
emitpcode(PC_CMPI, 0, b, 0);
branch_conditional(0, ENOTEQU, 1, caseranges[end].label);
I8_treecompare(r29, end);
} else {
PCodeLabel *label;
short a = ALLOC_GPR();
short b = ALLOC_GPR();
short c = ALLOC_GPR();
short d = ALLOC_GPR();
load_immediate(a, currange->min.lo);
load_immediate(b, currange->min.hi);
if (TYPE_INTEGRAL(selector_type)->integral != IT_ULONGLONG && TYPE_INTEGRAL(selector_type)->integral != IT_ULONGLONG) {
emitpcode(PC_XORIS, c, selector_gprHi, 0x8000);
emitpcode(PC_XORIS, d, b, 0x8000);
} else {
c = selector_gprHi;
d = b;
}
emitpcode(PC_SUBFC, a, a, selector_gpr);
emitpcode(PC_SUBFE, b, d, c);
emitpcode(PC_SUBFE, b, a, a);
emitpcode(PC_NEG, b, b);
emitpcode(PC_CMPI, 0, b, 0);
label = makepclabel();
branch_conditional(0, EEQU, 1, label);
I8_treecompare(start, r30);
branch_label(label);
I8_treecompare(r29, end);
}
}
}
static void generate_tree(ENode *expr) {
Operand op;
memclrw(&op, sizeof(Operand));
if (TYPE_IS_8BYTES(expr->rtype)) {
GEN_NODE(expr, &op);
coerce_to_register_pair(&op, expr->rtype, 0, 0);
selector_type = expr->rtype;
selector_gpr = op.reg;
selector_gprHi = op.regHi;
I8_treecompare(0, nranges_minus1);
} else {
GEN_NODE(expr, &op);
if (expr->rtype->size < 4)
extend32(&op, expr->rtype, 0);
ENSURE_GPR(&op, expr->rtype, 0);
selector_type = expr->rtype;
selector_gpr = op.reg;
treecompare(0, nranges_minus1);
}
}
static Object *create_switch_table(void) {
Object *obj;
ObjectList *list;
UInt32 *outptr;
CaseRange *currange;
SInt32 size;
CInt64 value;
obj = galloc(sizeof(Object));
list = galloc(sizeof(ObjectList));
memclrw(obj, sizeof(Object));
memclrw(list, sizeof(ObjectList));
obj->otype = OT_OBJECT;
obj->access = ACCESSPUBLIC;
obj->datatype = DDATA;
obj->name = CParser_GetUniqueName();
obj->toc = NULL;
obj->sclass = TK_STATIC;
obj->qual = Q_CONST;
obj->flags |= OBJECT_FLAGS_2 | OBJECT_DEFINED;
obj->u.data.linkname = obj->name;
obj->type = NULL;
createIndirect(obj, 0, 0);
obj->type = TYPE(&void_ptr);
size = CInt64_GetULong(&range) + 1;
obj->u.data.u.switchtable.size = size;
obj->u.data.u.switchtable.data = lalloc(4 * size);
currange = caseranges;
outptr = (UInt32 *) obj->u.data.u.switchtable.data;
value = cint64_zero;
while (CInt64_LessEqual(value, range)) {
while (CInt64_Greater(CInt64_Add(first, value), CInt64_Add(currange->min, currange->range)))
currange++;
*outptr = CTool_CreateIndexFromPointer(currange->label);
value = CInt64_Add(value, cint64_one);
outptr++;
}
list->object = obj;
list->next = switchtables;
switchtables = list;
return list->object;
}
static void generate_table(ENode *expr, SwitchInfo *info) {
Object *table;
SwitchCase *curcase;
short reg;
short reg2;
short reg3;
Operand op1;
Operand op2;
CInt64 val3 = {0, 3};
memclrw(&op1, sizeof(Operand));
memclrw(&op2, sizeof(Operand));
if (CInt64_Greater(first, cint64_zero) && CInt64_Less(first, val3)) {
range = CInt64_Add(range, first);
first = cint64_zero;
}
table = create_switch_table();
CError_ASSERT(553, !TYPE_IS_8BYTES(expr->rtype));
GEN_NODE(expr, &op1);
if (expr->rtype->size < 4)
extend32(&op1, expr->rtype, 0);
ENSURE_GPR(&op1, expr->rtype, 0);
reg = op1.reg;
if (CInt64_NotEqual(first, cint64_zero)) {
SInt32 value;
reg = ALLOC_GPR();
value = -CInt64_GetULong(&first);
if (!FITS_IN_SHORT(value)) {
emitpcode(PC_ADDIS, reg, op1.reg, 0, HIGH_PART(value));
if (value)
emitpcode(PC_ADDI, reg, reg, 0, LOW_PART(value));
} else {
emitpcode(PC_ADDI, reg, op1.reg, 0, value);
}
}
if (!FITS_IN_SHORT(CInt64_GetULong(&range))) {
short tmp = ALLOC_GPR();
load_immediate(tmp, CInt64_GetULong(&range));
emitpcode(PC_CMPL, 0, reg, tmp);
} else {
emitpcode(PC_CMPLI, 0, reg, CInt64_GetULong(&range));
}
branch_conditional(0, EGREATER, 1, defaultlabel);
if (table->toc) {
op2.optype = OpndType_Symbol;
op2.object = table->toc;
indirect(&op2, NULL);
} else {
op2.optype = OpndType_Symbol;
op2.object = table;
}
if (op2.optype != OpndType_GPR) {
Coerce_to_register(&op2, TYPE(&void_ptr), reg2 = ALLOC_GPR());
}
if (op2.optype != OpndType_GPR) {
CError_FATAL(599);
} else {
if (op2.reg != reg2)
emitpcode(PC_MR, reg2, op2.reg);
}
if (CInt64_Equal(first, cint64_zero)) {
reg = ALLOC_GPR();
emitpcode(PC_RLWINM, reg, op1.reg, 2, 0, 29);
} else {
emitpcode(PC_RLWINM, reg, reg, 2, 0, 29);
}
reg3 = reg2;
emitpcode(PC_LWZX, reg3, reg3, reg);
for (curcase = info->cases; curcase; curcase = curcase->next)
pcbranch(pclastblock, curcase->label->pclabel);
pcbranch(pclastblock, info->defaultlabel->pclabel);
emitpcode(PC_MTCTR, reg3);
branch_indirect(table);
}
void switchstatement(ENode *expr, SwitchInfo *info) {
Boolean use_table;
SwitchCase *swcase;
use_table = copts.switch_tables;
ncases = 0;
for (swcase = info->cases; swcase; swcase = swcase->next) {
if (!swcase->label->pclabel)
swcase->label->pclabel = makepclabel();
ncases++;
}
CError_ASSERT(656, ncases >= 0 && ncases <= 0x3333332U);
if (!info->defaultlabel->pclabel)
info->defaultlabel->pclabel = makepclabel();
defaultlabel = info->defaultlabel->pclabel;
build_case_ranges(expr->rtype, info->cases, info->defaultlabel);
if (TYPE_IS_8BYTES(expr->rtype)) {
generate_tree(expr);
return;
}
if (!use_table || nranges_minus1 < 8 || (nranges_minus1 * 2) < ((range.lo / 2) + 4))
generate_tree(expr);
else
generate_table(expr, info);
}
void dumpswitchtables(Object *funcobj) {
Object *table;
ObjectList *list;
SInt32 size;
UInt32 *array;
for (list = switchtables; list; list = list->next) {
table = list->object;
CError_ASSERT(694, table->otype == OT_OBJECT && table->access == ACCESSPUBLIC && table->datatype == DDATA);
size = table->u.data.u.switchtable.size;
array = (UInt32 *) table->u.data.u.switchtable.data;
while (size--) {
*array = CTool_EndianConvertWord32(((PCodeLabel *) CTool_ResolveIndexToPointer(*array))->block->codeOffset);
array++;
}
ObjGen_DeclareSwitchTable(table, funcobj);
}
}
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