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RISC-V: Cast ints to 32 bit integers when needed 

Mes defaults to 64 bit integers, which is perfectly OK according to the
C standard. TCC supposes ints are 32 bits, which is not necessarily true
and in Mes everything falls apart.

Casting intermediate values avoid this kind of issue and make TCC more
stable throughout C implementations. If we don't do this:

0b1001 << 30 >> 30
^^^^^^^^^^^^
this overflows in 32 bit integers but in 64 bit integers it doesn't.

Casting avoids this issue, truncating intermediate values.
This commit is contained in:
Ekaitz 2023-09-04 14:15:20 +02:00
parent 613c511c56
commit dc52a81586
1 changed files with 13 additions and 13 deletions
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26
riscv64-gen.c
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@ -343,11 +343,11 @@ static void load_large_constant(int rr, int fc, uint32_t pi)
if (fc < 0)
pi++;
o(0x37 | (rr << 7) | (((pi + 0x800) & 0xfffff000))); // lui RR, up(up(fc))
EI(0x13, 0, rr, rr, (int)pi << 20 >> 20); // addi RR, RR, lo(up(fc))
EI(0x13, 0, rr, rr, (int32_t)((int32_t)pi << 20) >> 20); // addi RR, RR, lo(up(fc))
EI(0x13, 1, rr, rr, 12); // slli RR, RR, 12
EI(0x13, 0, rr, rr, (fc + (1 << 19)) >> 20); // addi RR, RR, up(lo(fc))
EI(0x13, 0, rr, rr, (int32_t)(fc + (1 << 19)) >> 20); // addi RR, RR, up(lo(fc))
EI(0x13, 1, rr, rr, 12); // slli RR, RR, 12
fc = fc << 12 >> 12;
fc = (int32_t)((int32_t)fc << 12) >> 12;
EI(0x13, 0, rr, rr, fc >> 8); // addi RR, RR, lo1(lo(fc))
EI(0x13, 1, rr, rr, 8); // slli RR, RR, 8
}
@ -390,8 +390,8 @@ ST_FUNC void load(int r, SValue *sv)
load_large_constant(rr, fc, si);
fc &= 0xff;
} else {
o(0x37 | (rr << 7) | ((0x800 + fc) & 0xfffff000)); //lui RR, upper(fc)
fc = fc << 20 >> 20;
o(0x37 | (int32_t)(rr << 7) | ((0x800 + fc) & 0xfffff000)); //lui RR, upper(fc)
fc = (int32_t)(fc << 20) >> 20;
}
br = rr;
} else {
@ -425,7 +425,7 @@ ST_FUNC void load(int r, SValue *sv)
if (((unsigned)fc + (1 << 11)) >> 12)
o(0x37 | (rr << 7) | ((0x800 + fc) & 0xfffff000)), rb = rr; //lui RR, upper(fc)
if (fc || (rr != rb) || do32bit || (fr & VT_SYM))
EI(0x13 | do32bit, 0, rr, rb, fc << 20 >> 20); // addi[w] R, x0|R, FC
EI(0x13 | do32bit, 0, rr, rb, (int32_t)(fc << 20) >> 20); // addi[w] R, x0|R, FC
if (zext) {
EI(0x13, 1, rr, rr, 32); // slli RR, RR, 32
EI(0x13, 5, rr, rr, 32); // srli RR, RR, 32
@ -532,7 +532,7 @@ ST_FUNC void store(int r, SValue *sv)
fc &= 0xff;
} else {
o(0x37 | (ptrreg << 7) | ((0x800 + fc) & 0xfffff000)); //lui RR, upper(fc)
fc = fc << 20 >> 20;
fc = (int32_t)(fc << 20) >> 20;
}
} else
tcc_error("implement me: %s(!local)", "store");
@ -1045,7 +1045,7 @@ ST_FUNC void gfunc_epilog(void)
if (v >= (1 << 11)) {
d = 16;
o(0x37 | (5 << 7) | ((0x800 + (v-16)) & 0xfffff000)); //lui t0, upper(v)
EI(0x13, 0, 5, 5, (v-16) << 20 >> 20); // addi t0, t0, lo(v)
EI(0x13, 0, 5, 5, (int32_t)((v-16) << 20) >> 20); // addi t0, t0, lo(v)
ER(0x33, 0, 2, 2, 5, 0); // add sp, sp, t0
}
EI(0x03, 3, 1, 2, d - 8 - num_va_regs * 8); // ld ra, v-8(sp)
@ -1056,7 +1056,7 @@ ST_FUNC void gfunc_epilog(void)
if (v >= (1 << 11)) {
EI(0x13, 0, 8, 2, d - num_va_regs * 8); // addi s0, sp, d
o(0x37 | (5 << 7) | ((0x800 + (v-16)) & 0xfffff000)); //lui t0, upper(v)
EI(0x13, 0, 5, 5, (v-16) << 20 >> 20); // addi t0, t0, lo(v)
EI(0x13, 0, 5, 5, (int32_t)((v-16) << 20) >> 20); // addi t0, t0, lo(v)
ER(0x33, 0, 2, 2, 5, 0x20); // sub sp, sp, t0
gjmp_addr(func_sub_sp_offset + 5*4);
}
@ -1124,7 +1124,7 @@ static void gen_opil(int op, int ll)
ll = ll ? 0 : 8;
if ((vtop->r & (VT_VALMASK | VT_LVAL | VT_SYM)) == VT_CONST) {
int fc = vtop->c.i;
if (fc == vtop->c.i && !(((unsigned)fc + (1 << 11)) >> 12)) {
if (fc == vtop->c.i && !((uint32_t)((unsigned)fc + (1 << 11)) >> 12)) {
int cll = 0;
int m = ll ? 31 : 63;
vswap();
@ -1511,7 +1511,7 @@ ST_FUNC void gen_vla_sp_save(int addr)
if (((unsigned)addr + (1 << 11)) >> 12) {
o(0x37 | (5 << 7) | ((0x800 + addr) & 0xfffff000)); //lui t0,upper(addr)
ER(0x33, 0, 5, 5, 8, 0); // add t0, t0, s0
ES(0x23, 3, 5, 2, (int)addr << 20 >> 20); // sd sp, fc(t0)
ES(0x23, 3, 5, 2, (int32_t)((int32_t)addr << 20) >> 20); // sd sp, fc(t0)
}
else
ES(0x23, 3, 8, 2, addr); // sd sp, fc(s0)
@ -1519,10 +1519,10 @@ ST_FUNC void gen_vla_sp_save(int addr)
ST_FUNC void gen_vla_sp_restore(int addr)
{
if (((unsigned)addr + (1 << 11)) >> 12) {
if ((uint32_t)((uint32_t)addr + (1 << 11)) >> 12) {
o(0x37 | (5 << 7) | ((0x800 + addr) & 0xfffff000)); //lui t0,upper(addr)
ER(0x33, 0, 5, 5, 8, 0); // add t0, t0, s0
EI(0x03, 3, 2, 5, (int)addr << 20 >> 20); // ld sp, fc(t0)
EI(0x03, 3, 2, 5, (int32_t)((int32_t)addr << 20) >> 20); // ld sp, fc(t0)
}
else
EI(0x03, 3, 2, 8, addr); // ld sp, fc(s0)