From: David Gibson <david@gibson.dropbear.id.au>
To: peter.maydell@linaro.org, clg@kaod.org, danielhb413@gmail.com,
groug@kaod.org
Cc: Richard Henderson <richard.henderson@linaro.org>,
Luis Pires <luis.pires@eldorado.org.br>,
qemu-ppc@nongnu.org, qemu-devel@nongnu.org,
David Gibson <david@gibson.dropbear.id.au>
Subject: [PULL 16/54] libdecnumber: Introduce decNumberIntegralToInt128
Date: Tue, 9 Nov 2021 16:51:26 +1100 [thread overview]
Message-ID: <20211109055204.230765-17-david@gibson.dropbear.id.au> (raw)
In-Reply-To: <20211109055204.230765-1-david@gibson.dropbear.id.au>
From: Luis Pires <luis.pires@eldorado.org.br>
This will be used to implement PowerPC's dctfixqq.
Signed-off-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211029192417.400707-7-luis.pires@eldorado.org.br>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
include/libdecnumber/decNumber.h | 2 +
include/libdecnumber/decNumberLocal.h | 2 +-
libdecnumber/decContext.c | 7 +-
libdecnumber/decNumber.c | 95 +++++++++++++++++++++++++++
4 files changed, 102 insertions(+), 4 deletions(-)
diff --git a/include/libdecnumber/decNumber.h b/include/libdecnumber/decNumber.h
index 0cf69c7db2..41bc2a0d36 100644
--- a/include/libdecnumber/decNumber.h
+++ b/include/libdecnumber/decNumber.h
@@ -124,6 +124,8 @@
uint32_t decNumberToUInt32(const decNumber *, decContext *);
int32_t decNumberToInt32(const decNumber *, decContext *);
int64_t decNumberIntegralToInt64(const decNumber *dn, decContext *set);
+ void decNumberIntegralToInt128(const decNumber *dn, decContext *set,
+ uint64_t *plow, uint64_t *phigh);
uint8_t * decNumberGetBCD(const decNumber *, uint8_t *);
decNumber * decNumberSetBCD(decNumber *, const uint8_t *, uint32_t);
diff --git a/include/libdecnumber/decNumberLocal.h b/include/libdecnumber/decNumberLocal.h
index 4d53c077f2..6198ca8593 100644
--- a/include/libdecnumber/decNumberLocal.h
+++ b/include/libdecnumber/decNumberLocal.h
@@ -98,7 +98,7 @@
/* Shared lookup tables */
extern const uByte DECSTICKYTAB[10]; /* re-round digits if sticky */
- extern const uLong DECPOWERS[19]; /* powers of ten table */
+ extern const uLong DECPOWERS[20]; /* powers of ten table */
/* The following are included from decDPD.h */
extern const uShort DPD2BIN[1024]; /* DPD -> 0-999 */
extern const uShort BIN2DPD[1000]; /* 0-999 -> DPD */
diff --git a/libdecnumber/decContext.c b/libdecnumber/decContext.c
index 7d97a65ac5..1956edf0a7 100644
--- a/libdecnumber/decContext.c
+++ b/libdecnumber/decContext.c
@@ -53,12 +53,13 @@ static const Flag *mfctop=(Flag *)&mfcone; /* -> top byte */
const uByte DECSTICKYTAB[10]={1,1,2,3,4,6,6,7,8,9}; /* used if sticky */
/* ------------------------------------------------------------------ */
-/* Powers of ten (powers[n]==10**n, 0<=n<=9) */
+/* Powers of ten (powers[n]==10**n, 0<=n<=19) */
/* ------------------------------------------------------------------ */
-const uLong DECPOWERS[19] = {1, 10, 100, 1000, 10000, 100000, 1000000,
+const uLong DECPOWERS[20] = {1, 10, 100, 1000, 10000, 100000, 1000000,
10000000, 100000000, 1000000000, 10000000000ULL, 100000000000ULL,
1000000000000ULL, 10000000000000ULL, 100000000000000ULL, 1000000000000000ULL,
- 10000000000000000ULL, 100000000000000000ULL, 1000000000000000000ULL, };
+ 10000000000000000ULL, 100000000000000000ULL, 1000000000000000000ULL,
+ 10000000000000000000ULL,};
/* ------------------------------------------------------------------ */
/* decContextClearStatus -- clear bits in current status */
diff --git a/libdecnumber/decNumber.c b/libdecnumber/decNumber.c
index d7716ce175..31282adafd 100644
--- a/libdecnumber/decNumber.c
+++ b/libdecnumber/decNumber.c
@@ -264,6 +264,7 @@ static decNumber * decTrim(decNumber *, decContext *, Flag, Int *);
static Int decUnitAddSub(const Unit *, Int, const Unit *, Int, Int,
Unit *, Int);
static Int decUnitCompare(const Unit *, Int, const Unit *, Int, Int);
+static bool mulUInt128ByPowOf10(uLong *, uLong *, uInt);
#if !DECSUBSET
/* decFinish == decFinalize when no subset arithmetic needed */
@@ -542,6 +543,68 @@ Invalid:
return 0;
} /* decNumberIntegralToInt64 */
+/* ------------------------------------------------------------------ */
+/* decNumberIntegralToInt128 -- conversion to int128 */
+/* */
+/* dn is the decNumber to convert. dn is assumed to have been */
+/* rounded to a floating point integer value. */
+/* set is the context for reporting errors */
+/* returns the converted decNumber via plow and phigh */
+/* */
+/* Invalid is set if the decNumber is a NaN, Infinite or is out of */
+/* range for a signed 128 bit integer. */
+/* ------------------------------------------------------------------ */
+
+void decNumberIntegralToInt128(const decNumber *dn, decContext *set,
+ uint64_t *plow, uint64_t *phigh)
+{
+ int d; /* work */
+ const Unit *up; /* .. */
+ uint64_t lo = 0, hi = 0;
+
+ if (decNumberIsSpecial(dn) || (dn->exponent < 0) ||
+ (dn->digits + dn->exponent > 39)) {
+ goto Invalid;
+ }
+
+ up = dn->lsu; /* -> lsu */
+
+ for (d = (dn->digits - 1) / DECDPUN; d >= 0; d--) {
+ if (mulu128(&lo, &hi, DECDPUNMAX + 1)) {
+ /* overflow */
+ goto Invalid;
+ }
+ if (uadd64_overflow(lo, up[d], &lo)) {
+ if (uadd64_overflow(hi, 1, &hi)) {
+ /* overflow */
+ goto Invalid;
+ }
+ }
+ }
+
+ if (mulUInt128ByPowOf10(&lo, &hi, dn->exponent)) {
+ /* overflow */
+ goto Invalid;
+ }
+
+ if (decNumberIsNegative(dn)) {
+ if (lo == 0) {
+ *phigh = -hi;
+ *plow = 0;
+ } else {
+ *phigh = ~hi;
+ *plow = -lo;
+ }
+ } else {
+ *plow = lo;
+ *phigh = hi;
+ }
+
+ return;
+
+Invalid:
+ decContextSetStatus(set, DEC_Invalid_operation);
+} /* decNumberIntegralToInt128 */
/* ------------------------------------------------------------------ */
/* to-scientific-string -- conversion to numeric string */
@@ -7885,6 +7948,38 @@ static Int decGetDigits(Unit *uar, Int len) {
return digits;
} /* decGetDigits */
+/* ------------------------------------------------------------------ */
+/* mulUInt128ByPowOf10 -- multiply a 128-bit unsigned integer by a */
+/* power of 10. */
+/* */
+/* The 128-bit factor composed of plow and phigh is multiplied */
+/* by 10^exp. */
+/* */
+/* plow pointer to the low 64 bits of the first factor */
+/* phigh pointer to the high 64 bits of the first factor */
+/* exp the exponent of the power of 10 of the second factor */
+/* */
+/* If the result fits in 128 bits, returns false and the */
+/* multiplication result through plow and phigh. */
+/* Otherwise, returns true. */
+/* ------------------------------------------------------------------ */
+static bool mulUInt128ByPowOf10(uLong *plow, uLong *phigh, uInt pow10)
+{
+ while (pow10 >= ARRAY_SIZE(powers)) {
+ if (mulu128(plow, phigh, powers[ARRAY_SIZE(powers) - 1])) {
+ /* Overflow */
+ return true;
+ }
+ pow10 -= ARRAY_SIZE(powers) - 1;
+ }
+
+ if (pow10 > 0) {
+ return mulu128(plow, phigh, powers[pow10]);
+ } else {
+ return false;
+ }
+}
+
#if DECTRACE | DECCHECK
/* ------------------------------------------------------------------ */
/* decNumberShow -- display a number [debug aid] */
--
2.33.1
next prev parent reply other threads:[~2021-11-09 6:22 UTC|newest]
Thread overview: 60+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-11-09 5:51 [PULL 00/54] ppc-for-6.2 queue 20211109 David Gibson
2021-11-09 5:51 ` [PULL 01/54] target/ppc: introduce do_ea_calc David Gibson
2021-11-09 5:51 ` [PULL 02/54] target/ppc: move resolve_PLS_D to translate.c David Gibson
2021-11-09 5:51 ` [PULL 03/54] target/ppc: Move load and store floating point instructions to decodetree David Gibson
2021-11-10 16:33 ` Laurent Vivier
2021-11-10 16:56 ` Cédric Le Goater
2021-11-10 17:04 ` Laurent Vivier
2021-11-12 13:39 ` Cédric Le Goater
2021-11-09 5:51 ` [PULL 04/54] target/ppc: Implement PLFS, PLFD, PSTFS and PSTFD instructions David Gibson
2021-11-09 5:51 ` [PULL 05/54] target/ppc: Move LQ and STQ to decodetree David Gibson
2021-11-09 5:51 ` [PULL 06/54] target/ppc: Implement PLQ and PSTQ David Gibson
2021-11-09 5:51 ` [PULL 07/54] target/ppc: Implement cntlzdm David Gibson
2021-11-09 5:51 ` [PULL 08/54] target/ppc: Implement cnttzdm David Gibson
2021-11-09 5:51 ` [PULL 09/54] target/ppc: Implement pdepd instruction David Gibson
2021-11-09 5:51 ` [PULL 10/54] target/ppc: Implement pextd instruction David Gibson
2021-11-09 5:51 ` [PULL 11/54] libdecnumber: introduce decNumberFrom[U]Int128 David Gibson
2021-11-09 5:51 ` [PULL 12/54] target/ppc: Move REQUIRE_ALTIVEC/VECTOR to translate.c David Gibson
2021-11-09 5:51 ` [PULL 13/54] target/ppc: Introduce REQUIRE_FPU David Gibson
2021-11-09 5:51 ` [PULL 14/54] target/ppc: Implement DCFFIXQQ David Gibson
2021-11-09 5:51 ` [PULL 15/54] host-utils: Introduce mulu128 David Gibson
2021-11-09 5:51 ` David Gibson [this message]
2021-11-09 5:51 ` [PULL 17/54] target/ppc: Implement DCTFIXQQ David Gibson
2021-11-09 5:51 ` [PULL 18/54] target/ppc: Do not update nip on DFP instructions David Gibson
2021-11-09 5:51 ` [PULL 19/54] target/ppc: Move dtstdc[q]/dtstdg[q] to decodetree David Gibson
2021-11-09 5:51 ` [PULL 20/54] target/ppc: Move d{add, sub, mul, div, iex}[q] " David Gibson
2021-11-09 5:51 ` [PULL 21/54] target/ppc: Move dcmp{u, o}[q], dts{tex, tsf, tsfi}[q] " David Gibson
2021-11-09 5:51 ` [PULL 22/54] target/ppc: Move dquai[q], drint{x,n}[q] " David Gibson
2021-11-09 5:51 ` [PULL 23/54] target/ppc: Move dqua[q], drrnd[q] " David Gibson
2021-11-09 5:51 ` [PULL 24/54] target/ppc: Move dct{dp, qpq}, dr{sp, dpq}, dc{f, t}fix[q], dxex[q] " David Gibson
2021-11-09 5:51 ` [PULL 25/54] target/ppc: Move ddedpd[q], denbcd[q], dscli[q], dscri[q] " David Gibson
2021-11-09 5:51 ` [PULL 26/54] ppc/pnv: Fix check on block device before updating drive contents David Gibson
2021-11-09 5:51 ` [PULL 27/54] ppc/pegasos2: Suppress warning when qtest enabled David Gibson
2021-11-09 5:51 ` [PULL 28/54] target/ppc: Move vcfuged to vmx-impl.c.inc David Gibson
2021-11-09 5:51 ` [PULL 29/54] target/ppc: Implement vclzdm/vctzdm instructions David Gibson
2021-11-09 5:51 ` [PULL 30/54] target/ppc: Implement vpdepd/vpextd instruction David Gibson
2021-11-09 5:51 ` [PULL 31/54] target/ppc: Implement vsldbi/vsrdbi instructions David Gibson
2021-11-09 5:51 ` [PULL 32/54] target/ppc: Implement Vector Insert from GPR using GPR index insns David Gibson
2021-11-09 5:51 ` [PULL 33/54] target/ppc: Implement Vector Insert Word from GPR using Immediate insns David Gibson
2021-11-09 5:51 ` [PULL 34/54] target/ppc: Implement Vector Insert from VSR using GPR index insns David Gibson
2021-11-09 5:51 ` [PULL 35/54] target/ppc: Move vinsertb/vinserth/vinsertw/vinsertd to decodetree David Gibson
2021-11-09 5:51 ` [PULL 36/54] target/ppc: Implement Vector Extract Double to VSR using GPR index insns David Gibson
2021-11-09 5:51 ` [PULL 37/54] target/ppc: Introduce REQUIRE_VSX macro David Gibson
2021-11-09 5:51 ` [PULL 38/54] target/ppc: receive high/low as argument in get/set_cpu_vsr David Gibson
2021-11-09 5:51 ` [PULL 39/54] target/ppc: moved stxv and lxv from legacy to decodtree David Gibson
2021-11-09 5:51 ` [PULL 40/54] target/ppc: moved stxvx and lxvx " David Gibson
2021-11-09 5:51 ` [PULL 41/54] target/ppc: added the instructions LXVP and STXVP David Gibson
2021-11-09 5:51 ` [PULL 42/54] target/ppc: added the instructions LXVPX and STXVPX David Gibson
2021-11-09 5:51 ` [PULL 43/54] target/ppc: added the instructions PLXV and PSTXV David Gibson
2021-11-09 5:51 ` [PULL 44/54] target/ppc: added the instructions PLXVP and PSTXVP David Gibson
2021-11-09 5:51 ` [PULL 45/54] target/ppc: moved XXSPLTW to using decodetree David Gibson
2021-11-09 5:51 ` [PULL 46/54] target/ppc: moved XXSPLTIB " David Gibson
2021-11-09 5:51 ` [PULL 47/54] target/ppc: implemented XXSPLTI32DX David Gibson
2021-11-09 5:51 ` [PULL 48/54] target/ppc: Implemented XXSPLTIW using decodetree David Gibson
2021-11-09 5:51 ` [PULL 49/54] target/ppc: implemented XXSPLTIDP instruction David Gibson
2021-11-09 5:52 ` [PULL 50/54] target/ppc: Implement xxblendvb/xxblendvh/xxblendvw/xxblendvd instructions David Gibson
2021-11-09 5:52 ` [PULL 51/54] target/ppc: Implement lxvkq instruction David Gibson
2021-11-09 5:52 ` [PULL 52/54] target/ppc: cntlzdm/cnttzdm implementation without brcond David Gibson
2021-11-09 5:52 ` [PULL 53/54] target/ppc, hw/ppc: Change maintainers David Gibson
2021-11-09 5:52 ` [PULL 54/54] spapr_numa.c: FORM2 table handle nodes with no distance info David Gibson
2021-11-09 8:41 ` [PULL 00/54] ppc-for-6.2 queue 20211109 Richard Henderson
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