target-ppc: Add ISA2.06 divdeu[o] Instructions

This patch adds the Divide Doubleword Extended Unsigned
instructions.  This instruction requires dividing a 128-bit
value by a 64 bit value.  Since 128 bit integer division is
not supported in TCG, a helper is used.  An architecture
independent 128-bit division routine is added to host-utils.

Signed-off-by: Tom Musta <tommusta@gmail.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
[agraf: use ||]
Signed-off-by: Alexander Graf <agraf@suse.de>
This commit is contained in:
Tom Musta 2014-01-07 10:05:51 -06:00 committed by Alexander Graf
parent a824bc191a
commit 98d1eb2748
5 changed files with 101 additions and 0 deletions

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@ -44,9 +44,23 @@ static inline void muls64(uint64_t *plow, uint64_t *phigh,
*plow = r;
*phigh = r >> 64;
}
static inline int divu128(uint64_t *plow, uint64_t *phigh, uint64_t divisor)
{
if (divisor == 0) {
return 1;
} else {
__uint128_t dividend = ((__uint128_t)*phigh << 64) | *plow;
__uint128_t result = dividend / divisor;
*plow = result;
*phigh = dividend % divisor;
return result > UINT64_MAX;
}
}
#else
void muls64(uint64_t *phigh, uint64_t *plow, int64_t a, int64_t b);
void mulu64(uint64_t *phigh, uint64_t *plow, uint64_t a, uint64_t b);
int divu128(uint64_t *plow, uint64_t *phigh, uint64_t divisor);
#endif
/**

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@ -31,6 +31,7 @@ DEF_HELPER_5(lscbx, tl, env, tl, i32, i32, i32)
#if defined(TARGET_PPC64)
DEF_HELPER_3(mulldo, i64, env, i64, i64)
DEF_HELPER_4(divdeu, i64, env, i64, i64, i32)
#endif
DEF_HELPER_FLAGS_1(cntlzw, TCG_CALL_NO_RWG_SE, tl, tl)

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@ -41,6 +41,33 @@ uint64_t helper_mulldo(CPUPPCState *env, uint64_t arg1, uint64_t arg2)
}
#endif
#if defined(TARGET_PPC64)
uint64_t helper_divdeu(CPUPPCState *env, uint64_t ra, uint64_t rb, uint32_t oe)
{
uint64_t rt = 0;
int overflow = 0;
overflow = divu128(&rt, &ra, rb);
if (unlikely(overflow)) {
rt = 0; /* Undefined */
}
if (oe) {
if (unlikely(overflow)) {
env->so = env->ov = 1;
} else {
env->ov = 0;
}
}
return rt;
}
#endif
target_ulong helper_cntlzw(target_ulong t)
{
return clz32(t);

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@ -984,6 +984,20 @@ GEN_INT_ARITH_DIVW(divwuo, 0x1E, 0, 1);
/* divw divw. divwo divwo. */
GEN_INT_ARITH_DIVW(divw, 0x0F, 1, 0);
GEN_INT_ARITH_DIVW(divwo, 0x1F, 1, 1);
/* div[wd]eu[o][.] */
#define GEN_DIVE(name, hlpr, compute_ov) \
static void gen_##name(DisasContext *ctx) \
{ \
TCGv_i32 t0 = tcg_const_i32(compute_ov); \
gen_helper_##hlpr(cpu_gpr[rD(ctx->opcode)], cpu_env, \
cpu_gpr[rA(ctx->opcode)], cpu_gpr[rB(ctx->opcode)], t0); \
tcg_temp_free_i32(t0); \
if (unlikely(Rc(ctx->opcode) != 0)) { \
gen_set_Rc0(ctx, cpu_gpr[rD(ctx->opcode)]); \
} \
}
#if defined(TARGET_PPC64)
static inline void gen_op_arith_divd(DisasContext *ctx, TCGv ret, TCGv arg1,
TCGv arg2, int sign, int compute_ov)
@ -1032,6 +1046,10 @@ GEN_INT_ARITH_DIVD(divduo, 0x1E, 0, 1);
/* divw divw. divwo divwo. */
GEN_INT_ARITH_DIVD(divd, 0x0F, 1, 0);
GEN_INT_ARITH_DIVD(divdo, 0x1F, 1, 1);
GEN_DIVE(divdeu, divdeu, 0);
GEN_DIVE(divdeuo, divdeu, 1);
#endif
/* mulhw mulhw. */
@ -9707,6 +9725,9 @@ GEN_INT_ARITH_DIVD(divduo, 0x1E, 0, 1),
GEN_INT_ARITH_DIVD(divd, 0x0F, 1, 0),
GEN_INT_ARITH_DIVD(divdo, 0x1F, 1, 1),
GEN_HANDLER_E(divdeu, 0x1F, 0x09, 0x0C, 0, PPC_NONE, PPC2_DIVE_ISA206),
GEN_HANDLER_E(divdeuo, 0x1F, 0x09, 0x1C, 0, PPC_NONE, PPC2_DIVE_ISA206),
#undef GEN_INT_ARITH_MUL_HELPER
#define GEN_INT_ARITH_MUL_HELPER(name, opc3) \
GEN_HANDLER(name, 0x1F, 0x09, opc3, 0x00000000, PPC_64B)

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@ -86,4 +86,42 @@ void muls64 (uint64_t *plow, uint64_t *phigh, int64_t a, int64_t b)
}
*phigh = rh;
}
/* Unsigned 128x64 division. Returns 1 if overflow (divide by zero or */
/* quotient exceeds 64 bits). Otherwise returns quotient via plow and */
/* remainder via phigh. */
int divu128(uint64_t *plow, uint64_t *phigh, uint64_t divisor)
{
uint64_t dhi = *phigh;
uint64_t dlo = *plow;
unsigned i;
uint64_t carry = 0;
if (divisor == 0) {
return 1;
} else if (dhi == 0) {
*plow = dlo / divisor;
*phigh = dlo % divisor;
return 0;
} else if (dhi > divisor) {
return 1;
} else {
for (i = 0; i < 64; i++) {
carry = dhi >> 63;
dhi = (dhi << 1) | (dlo >> 63);
if (carry || (dhi >= divisor)) {
dhi -= divisor;
carry = 1;
} else {
carry = 0;
}
dlo = (dlo << 1) | carry;
}
*plow = dlo;
*phigh = dhi;
return 0;
}
}
#endif /* !CONFIG_INT128 */