riscv: TLC of param passing

factor and cleanup the param passing code somewhat.
This commit is contained in:
Michael Matz 2019-08-11 01:54:29 +02:00
parent c505074a9f
commit 83cf5bf17f
2 changed files with 73 additions and 117 deletions

View File

@ -433,20 +433,20 @@ static void gcall_or_jmp(int docall)
}
}
static void reg_pass(CType *type, int *rc, int *fieldofs, int ofs)
static void reg_pass_rec(CType *type, int *rc, int *fieldofs, int ofs)
{
if ((type->t & VT_BTYPE) == VT_STRUCT) {
Sym *f;
if (type->ref->type.t == VT_UNION)
rc[0] = -1;
else for (f = type->ref->next; f; f = f->next)
reg_pass(&f->type, rc, fieldofs, ofs + f->c);
reg_pass_rec(&f->type, rc, fieldofs, ofs + f->c);
} else if (type->t & VT_ARRAY) {
if (type->ref->c < 0 || type->ref->c > 2)
rc[0] = -1;
else {
int a, sz = type_size(&type->ref->type, &a);
reg_pass(&type->ref->type, rc, fieldofs, ofs);
reg_pass_rec(&type->ref->type, rc, fieldofs, ofs);
if (rc[0] > 2 || (rc[0] == 2 && type->ref->c > 1))
rc[0] = -1;
else if (type->ref->c == 2 && rc[0] && rc[1] == RC_FLOAT) {
@ -465,20 +465,32 @@ static void reg_pass(CType *type, int *rc, int *fieldofs, int ofs)
rc[0] = -1;
}
static void reg_pass(CType *type, int *prc, int *fieldofs, int named)
{
prc[0] = 0;
reg_pass_rec(type, prc, fieldofs, 0);
if (prc[0] <= 0 || !named) {
int align, size = type_size(type, &align);
prc[0] = (size + 7) >> 3;
prc[1] = prc[2] = RC_INT;
fieldofs[1] = (0 << 4) | (size <= 1 ? VT_BYTE : size <= 2 ? VT_SHORT : size <= 4 ? VT_INT : VT_LLONG);
fieldofs[2] = (8 << 4) | (size <= 9 ? VT_BYTE : size <= 10 ? VT_SHORT : size <= 12 ? VT_INT : VT_LLONG);
}
}
ST_FUNC void gfunc_call(int nb_args)
{
int i, align, size, aireg, afreg;
int i, align, size, areg[2];
int info[nb_args ? nb_args : 1];
int stack_adj = 0, tempspace = 0, ofs, splitofs = 0;
int force_stack = 0;
SValue *sv;
Sym *sa;
aireg = afreg = 0;
areg[0] = 0; /* int arg regs */
areg[1] = 8; /* float arg regs */
sa = vtop[-nb_args].type.ref->next;
for (i = 0; i < nb_args; i++) {
int *pareg, nregs, byref = 0, tempofs;
int nregs, byref = 0, tempofs;
int prc[3], fieldofs[3];
prc[0] = 0;
sv = &vtop[1 + i - nb_args];
sv->type.t &= ~VT_ARRAY; // XXX this should be done in tccgen.c
size = type_size(&sv->type, &align);
@ -489,53 +501,43 @@ ST_FUNC void gfunc_call(int nb_args)
tempofs = tempspace;
tempspace += size;
size = align = 8;
byref = 1;
}
if (size > 8)
nregs = 2;
else
nregs = 1;
if (!sa) {
prc[0] = nregs, prc[1] = prc[2] = RC_INT;
} else {
reg_pass(&sv->type, prc, fieldofs, 0);
if (prc[0] < 0)
prc[0] = nregs, prc[1] = prc[2] = RC_INT;
byref = 64 | (tempofs << 7);
}
reg_pass(&sv->type, prc, fieldofs, sa != 0);
if (!sa && align == 2*XLEN && size <= 2*XLEN)
aireg = (aireg + 1) & ~1;
areg[0] = (areg[0] + 1) & ~1;
nregs = prc[0];
assert(nregs);
if (!nregs
|| (prc[1] == RC_INT && aireg >= 8)
|| (prc[1] == RC_FLOAT && afreg >= 8)
|| (nregs == 2 && prc[2] == RC_FLOAT && afreg >= 7)
|| (nregs == 2 && prc[1] != prc[2] && (afreg >= 8 || aireg >= 8))
|| force_stack) {
if ((prc[1] == RC_INT && areg[0] >= 8)
|| (prc[1] == RC_FLOAT && areg[1] >= 16)
|| (nregs == 2 && prc[1] == RC_FLOAT && prc[2] == RC_FLOAT
&& areg[1] >= 15)
|| (nregs == 2 && prc[1] != prc[2]
&& (areg[1] >= 16 || areg[0] >= 8))) {
info[i] = 32;
if (align < XLEN)
align = XLEN;
stack_adj += (size + align - 1) & -align;
if (!sa)
force_stack = 1;
if (!sa) /* one vararg on stack forces the rest on stack */
areg[0] = 8, areg[1] = 16;
} else {
if (prc[1] == RC_FLOAT)
info[i] = 8 + afreg++;
else
info[i] = aireg++;
info[i] = areg[prc[1] - 1]++;
if (!byref)
info[i] |= (fieldofs[1] & VT_BTYPE) << 12;
assert(!(fieldofs[1] >> 4));
if (nregs == 2) {
if (prc[2] == RC_FLOAT)
info[i] |= (1 + 8 + afreg++) << 7;
else if (aireg < 8)
info[i] |= (1 + aireg++) << 7;
if (prc[2] == RC_FLOAT || areg[0] < 8)
info[i] |= (1 + areg[prc[2] - 1]++) << 7;
else {
info[i] |= 16;
stack_adj += 8;
}
if (!byref) {
assert((fieldofs[2] >> 4) < 2048);
info[i] |= fieldofs[2] << (12 + 4); // includes offset
}
}
}
if (byref)
info[i] |= 64 | (tempofs << 7);
info[i] |= byref;
if (sa)
sa = sa->next;
}
@ -544,7 +546,7 @@ ST_FUNC void gfunc_call(int nb_args)
if (stack_adj + tempspace) {
EI(0x13, 0, 2, 2, -(stack_adj + tempspace)); // addi sp, sp, -adj
for (i = ofs = 0; i < nb_args; i++) {
if (info[i] >= 32) {
if (info[i] & (64 | 32)) {
vrotb(nb_args - i);
size = type_size(&vtop->type, &align);
if (info[i] & 64) {
@ -587,26 +589,19 @@ ST_FUNC void gfunc_call(int nb_args)
}
}
for (i = 0; i < nb_args; i++) {
int r = info[nb_args - 1 - i], r2 = r;
int ii = info[nb_args - 1 - i], r = ii, r2 = r;
if (!(r & 32)) {
CType origtype;
int prc[3], fieldofs[3], loadt;
prc[0] = 0;
int loadt;
r &= 15;
r2 = r2 & 64 ? 0 : r2 >> 7;
r2 = r2 & 64 ? 0 : (r2 >> 7) & 31;
assert(r2 <= 16);
vrotb(i+1);
origtype = vtop->type;
size = type_size(&vtop->type, &align);
reg_pass(&vtop->type, prc, fieldofs, 0);
if (prc[0] <= 0 || (!r2 && prc[0] > 1)) {
prc[0] = (size + 7) >> 3;
prc[1] = prc[2] = RC_INT;
fieldofs[1] = (0 << 4) | (size <= 1 ? VT_BYTE : size <= 2 ? VT_SHORT : size <= 4 ? VT_INT : VT_LLONG);
fieldofs[2] = (8 << 4) | (size <= 9 ? VT_BYTE : size <= 10 ? VT_SHORT : size <= 12 ? VT_INT : VT_LLONG);
}
loadt = vtop->type.t & VT_BTYPE;
if (loadt == VT_STRUCT) {
loadt = fieldofs[1] & VT_BTYPE;
loadt = (ii >> 12) & VT_BTYPE;
}
if (info[nb_args - 1 - i] & 16) {
assert(!r2);
@ -629,13 +624,13 @@ ST_FUNC void gfunc_call(int nb_args)
vswap();
gaddrof();
vtop->type = char_pointer_type;
vpushi(fieldofs[2] >> 4);
vpushi(ii >> 20);
gen_op('+');
indir();
vtop->type = origtype;
loadt = vtop->type.t & VT_BTYPE;
if (loadt == VT_STRUCT) {
loadt = fieldofs[2] & VT_BTYPE;
loadt = (ii >> 16) & VT_BTYPE;
}
save_reg_upstack(r2, 1);
vtop->type.t = loadt;
@ -671,7 +666,7 @@ ST_FUNC void gfunc_prolog(CType *func_type)
{
int i, addr, align, size;
int param_addr = 0;
int aireg, afreg;
int areg[2];
Sym *sym;
CType *type;
@ -681,69 +676,51 @@ ST_FUNC void gfunc_prolog(CType *func_type)
func_sub_sp_offset = ind;
ind += 5 * 4;
aireg = afreg = 0;
addr = 0; // XXX not correct
areg[0] = 0, areg[1] = 0;
addr = 0;
/* if the function returns by reference, then add an
implicit pointer parameter */
size = type_size(&func_vt, &align);
if (size > 2 * XLEN) {
loc -= 8;
func_vc = loc;
ES(0x23, 3, 8, 10 + aireg, loc); // sd a0, loc(s0)
aireg++;
ES(0x23, 3, 8, 10 + areg[0]++, loc); // sd a0, loc(s0)
}
/* define parameters */
while ((sym = sym->next) != NULL) {
int byref = 0;
int regcount;
int prc[3], fieldofs[3];
type = &sym->type;
size = type_size(type, &align);
if (size > 2 * XLEN) {
type = &char_pointer_type;
size = align = byref = 8;
}
if (size > 2 * XLEN) {
from_stack:
reg_pass(type, prc, fieldofs, 1);
regcount = prc[0];
if (areg[prc[1] - 1] >= 8
|| (regcount == 2
&& ((prc[1] == RC_FLOAT && prc[2] == RC_FLOAT && areg[1] >= 7)
|| (prc[1] != prc[2] && (areg[1] >= 8 || areg[0] >= 8))))) {
if (align < XLEN)
align = XLEN;
addr = (addr + align - 1) & -align;
param_addr = addr;
addr += size;
} else {
int regcount, *pareg;
int prc[3], fieldofs[3];
prc[0] = 0;
reg_pass(type, prc, fieldofs, 0);
if (prc[0] <= 0) {
prc[0] = (size + 7) >> 3;
prc[1] = prc[2] = RC_INT;
fieldofs[1] = (0 << 4) | (size <= 1 ? VT_BYTE : size <= 2 ? VT_SHORT : size <= 4 ? VT_INT : VT_LLONG);
fieldofs[2] = (8 << 4) | (size <= 9 ? VT_BYTE : size <= 10 ? VT_SHORT : size <= 12 ? VT_INT : VT_LLONG);
}
regcount = prc[0];
if (!regcount
|| (prc[1] == RC_INT && aireg >= 8)
|| (prc[1] == RC_FLOAT && afreg >= 8)
|| (regcount == 2 && prc[2] == RC_FLOAT && afreg >= 7)
|| (regcount == 2 && prc[1] != prc[2] && (afreg >= 8 || aireg >= 8)))
goto from_stack;
if (size > XLEN)
assert(regcount == 2);
loc -= regcount * 8; // XXX could reserve only 'size' bytes
param_addr = loc;
for (i = 0; i < regcount; i++) {
pareg = prc[1+i] == RC_INT ? &aireg : &afreg;
if (*pareg >= 8) {
if (areg[prc[1+i] - 1] >= 8) {
assert(i == 1 && regcount == 2 && !(addr & 7));
EI(0x03, 3, 5, 8, addr); // ld t0, addr(s0)
addr += 8;
ES(0x23, 3, 8, 5, loc + i*8); // sd t0, loc(s0)
continue;
}
if (pareg == &afreg) {
//assert(type->t == VT_FLOAT || type->t == VT_DOUBLE);
ES(0x27, (size / regcount) == 4 ? 2 : 3, 8, 10 + afreg++, loc + (fieldofs[i+1] >> 4)); // fs[wd] FAi, loc(s0)
} else if (prc[1+i] == RC_FLOAT) {
ES(0x27, (size / regcount) == 4 ? 2 : 3, 8, 10 + areg[1]++, loc + (fieldofs[i+1] >> 4)); // fs[wd] FAi, loc(s0)
} else {
ES(0x23, 3, 8, 10 + aireg++, loc + i*8); // sd aX, loc(s0) // XXX
ES(0x23, 3, 8, 10 + areg[0]++, loc + i*8); // sd aX, loc(s0) // XXX
}
}
}
@ -754,9 +731,9 @@ ST_FUNC void gfunc_prolog(CType *func_type)
func_va_list_ofs = addr;
num_va_regs = 0;
if (func_type->ref->f.func_type == FUNC_ELLIPSIS) {
for (; aireg < 8; aireg++) {
for (; areg[0] < 8; areg[0]++) {
num_va_regs++;
ES(0x23, 3, 8, 10 + aireg, -8 + num_va_regs * 8); // sd aX, loc(s0)
ES(0x23, 3, 8, 10 + areg[0], -8 + num_va_regs * 8); // sd aX, loc(s0)
}
}
}
@ -764,22 +741,14 @@ ST_FUNC void gfunc_prolog(CType *func_type)
ST_FUNC int gfunc_sret(CType *vt, int variadic, CType *ret,
int *ret_align, int *regsize)
{
int align, size = type_size(vt, &align), infreg, nregs;
int align, size = type_size(vt, &align), nregs;
int prc[3], fieldofs[3];
*ret_align = 1;
*regsize = 8;
if (size > 16)
return 0;
prc[0] = 0;
reg_pass(vt, prc, fieldofs, 0);
if (prc[0] <= 0) {
prc[0] = (size + 7) >> 3;
prc[1] = prc[2] = RC_INT;
fieldofs[1] = (0 << 4) | (size <= 1 ? VT_BYTE : size <= 2 ? VT_SHORT : size <= 4 ? VT_INT : VT_LLONG);
fieldofs[2] = (8 << 4) | (size <= 9 ? VT_BYTE : size <= 10 ? VT_SHORT : size <= 12 ? VT_INT : VT_LLONG);
}
reg_pass(vt, prc, fieldofs, 1);
nregs = prc[0];
assert(nregs > 0);
if (nregs == 2 && prc[1] != prc[2])
return -1; /* generic code can't deal with this case */
if (prc[1] == RC_FLOAT) {
@ -792,22 +761,15 @@ ST_FUNC int gfunc_sret(CType *vt, int variadic, CType *ret,
ST_FUNC void arch_transfer_ret_regs(int aftercall)
{
int prc[3], fieldofs[3];
prc[0] = 0;
reg_pass(&vtop->type, prc, fieldofs, 0);
reg_pass(&vtop->type, prc, fieldofs, 1);
assert(prc[0] == 2 && prc[1] != prc[2] && !(fieldofs[1] >> 4));
assert(vtop->r == (VT_LOCAL | VT_LVAL));
vpushv(vtop);
vtop->type.t = fieldofs[1] & VT_BTYPE;
if (aftercall)
store(prc[1] == RC_INT ? REG_IRET : REG_FRET, vtop);
else
load(prc[1] == RC_INT ? REG_IRET : REG_FRET, vtop);
(aftercall ? store : load)(prc[1] == RC_INT ? REG_IRET : REG_FRET, vtop);
vtop->c.i += fieldofs[2] >> 4;
vtop->type.t = fieldofs[2] & VT_BTYPE;
if (aftercall)
store(prc[2] == RC_INT ? REG_IRET : REG_FRET, vtop);
else
load(prc[2] == RC_INT ? REG_IRET : REG_FRET, vtop);
(aftercall ? store : load)(prc[2] == RC_INT ? REG_IRET : REG_FRET, vtop);
vtop--;
}
@ -857,11 +819,6 @@ ST_FUNC void gen_va_start(void)
vset(&char_pointer_type, VT_LOCAL, func_va_list_ofs);
}
ST_FUNC void gen_va_arg(CType *t)
{
tcc_error("implement me: %s", __FUNCTION__);
}
ST_FUNC void gen_fill_nops(int bytes)
{
if ((bytes & 3))

1
tcc.h
View File

@ -1606,7 +1606,6 @@ ST_FUNC void gen_cvt_sxtw(void);
ST_FUNC void gen_opl(int op);
//ST_FUNC void gfunc_return(CType *func_type);
ST_FUNC void gen_va_start(void);
ST_FUNC void gen_va_arg(CType *t);
ST_FUNC void arch_transfer_ret_regs(int);
#endif
/* ------------ c67-gen.c ------------ */