Reduce stack size of DecimalSymbolsV1 (#5804)

Fixes #4437


This doesn't work yet: there's no easy way to get Bake impls for custom
VarULE types since `from_byte_slice_unchecked` can't be called in const
contexts (since you can't do trait stuff in non-const contexts: in
theory this function is very const-capable)

I chose to use `make_varule` but VarTupleNULE would work as well (and
plus we can give it the relevant Bake impl if we want). I wrote this PR
to encapsulate things so that swapping the internals is easier

I think I'll make this work by implementing ZeroCow:
#5561


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components/datetime/src/external_loaders.rs

@@ -113,7 +113,7 @@ pub(crate) struct ExternalLoaderUnstable<'a, P: ?Sized>(pub &'a P);
 
 impl<P> FixedDecimalFormatterLoader for ExternalLoaderUnstable<'_, P>
 where
-    P: ?Sized + DataProvider<icu_decimal::provider::DecimalSymbolsV1Marker>,
+    P: ?Sized + DataProvider<icu_decimal::provider::DecimalSymbolsV2Marker>,
 {
     #[inline]
     fn load(

components/datetime/src/format/neo.rs

@@ -30,7 +30,7 @@ use icu_calendar::types::FormattingEra;
 use icu_calendar::types::MonthCode;
 use icu_decimal::options::FixedDecimalFormatterOptions;
 use icu_decimal::options::GroupingStrategy;
-use icu_decimal::provider::DecimalSymbolsV1Marker;
+use icu_decimal::provider::DecimalSymbolsV2Marker;
 use icu_decimal::FixedDecimalFormatter;
 use icu_provider::marker::NeverMarker;
 use icu_provider::prelude::*;
@@ -262,7 +262,7 @@ where
 size_test!(
     TypedDateTimeNames<icu_calendar::Gregorian, DateTimeMarker>,
     typed_date_time_names_size,
-    456
+    336
 );
 
 /// A low-level type that formats datetime patterns with localized names.
@@ -625,7 +625,7 @@ impl<C: CldrCalendar, R: DateTimeNamesMarker> TypedDateTimeNames<C, R> {
     #[doc = icu_provider::gen_any_buffer_unstable_docs!(UNSTABLE, Self::try_new)]
     pub fn try_new_unstable<P>(provider: &P, locale: &DataLocale) -> Result<Self, DataError>
     where
-        P: DataProvider<DecimalSymbolsV1Marker> + ?Sized,
+        P: DataProvider<DecimalSymbolsV2Marker> + ?Sized,
     {
         let mut names = Self {
             locale: locale.clone(),
@@ -1418,7 +1418,7 @@ impl<C: CldrCalendar, R: DateTimeNamesMarker> TypedDateTimeNames<C, R> {
     #[inline]
     pub fn load_fixed_decimal_formatter<P>(&mut self, provider: &P) -> Result<&mut Self, DataError>
     where
-        P: DataProvider<DecimalSymbolsV1Marker> + ?Sized,
+        P: DataProvider<DecimalSymbolsV2Marker> + ?Sized,
     {
         self.inner
             .load_fixed_decimal_formatter(&ExternalLoaderUnstable(provider), &self.locale)?;
@@ -1497,7 +1497,7 @@ impl<C: CldrCalendar, R: DateTimeNamesMarker> TypedDateTimeNames<C, R> {
             + DataProvider<tz::MzSpecificLongV1Marker>
             + DataProvider<tz::MzSpecificShortV1Marker>
             + DataProvider<tz::MzPeriodV1Marker>
-            + DataProvider<DecimalSymbolsV1Marker>
+            + DataProvider<DecimalSymbolsV2Marker>
             + ?Sized,
     {
         let locale = &self.locale;

components/datetime/src/neo.rs

@@ -132,7 +132,7 @@ macro_rules! gen_any_buffer_constructors_with_external_loader {
 //     }
 // }
 
-size_test!(FixedCalendarDateTimeFormatter<icu_calendar::Gregorian, crate::fieldset::YMD>, typed_neo_year_month_day_formatter_size, 456);
+size_test!(FixedCalendarDateTimeFormatter<icu_calendar::Gregorian, crate::fieldset::YMD>, typed_neo_year_month_day_formatter_size, 336);
 
 /// [`FixedCalendarDateTimeFormatter`] is a formatter capable of formatting dates and/or times from
 /// a calendar selected at compile time.
@@ -352,7 +352,7 @@ where
 size_test!(
     DateTimeFormatter<crate::fieldset::YMD>,
     neo_year_month_day_formatter_size,
-    512
+    392
 );
 
 /// [`DateTimeFormatter`] is a formatter capable of formatting dates and/or times from

components/datetime/src/scaffold/fieldset_traits.rs

@@ -18,7 +18,7 @@ use icu_calendar::{
     },
     Date, Iso, Time,
 };
-use icu_decimal::provider::DecimalSymbolsV1Marker;
+use icu_decimal::provider::DecimalSymbolsV2Marker;
 use icu_provider::{marker::NeverMarker, prelude::*};
 use icu_timezone::scaffold::IntoOption;
 use icu_timezone::{TimeZoneBcp47Id, UtcOffset, ZoneVariant};
@@ -368,10 +368,10 @@ where
 
 /// Trait to consolidate data provider markers external to this crate
 /// for datetime formatting with a fixed calendar.
-pub trait AllFixedCalendarExternalDataMarkers: DataProvider<DecimalSymbolsV1Marker> {}
+pub trait AllFixedCalendarExternalDataMarkers: DataProvider<DecimalSymbolsV2Marker> {}
 
 impl<T> AllFixedCalendarExternalDataMarkers for T where
-    T: ?Sized + DataProvider<DecimalSymbolsV1Marker>
+    T: ?Sized + DataProvider<DecimalSymbolsV2Marker>
 {
 }
 
@@ -384,7 +384,7 @@ pub trait AllAnyCalendarExternalDataMarkers:
     + DataProvider<IslamicUmmAlQuraCacheV1Marker>
     + DataProvider<JapaneseErasV1Marker>
     + DataProvider<JapaneseExtendedErasV1Marker>
-    + DataProvider<DecimalSymbolsV1Marker>
+    + DataProvider<DecimalSymbolsV2Marker>
 {
 }
 
@@ -396,7 +396,7 @@ impl<T> AllAnyCalendarExternalDataMarkers for T where
         + DataProvider<IslamicUmmAlQuraCacheV1Marker>
         + DataProvider<JapaneseErasV1Marker>
         + DataProvider<JapaneseExtendedErasV1Marker>
-        + DataProvider<DecimalSymbolsV1Marker>
+        + DataProvider<DecimalSymbolsV2Marker>
 {
 }
 

components/datetime/tests/data/gen.sh

@@ -5,7 +5,7 @@ GregorianDateLengthsV1Marker \
 GregorianDateSymbolsV1Marker \
 TimeLengthsV1Marker \
 TimeSymbolsV1Marker \
-DecimalSymbolsV1Marker \
+DecimalSymbolsV2Marker \
 TimeZoneFormatsV1Marker \
 MetazoneSpecificNamesShortV1Marker \
 --locales en \

components/decimal/Cargo.toml

@@ -24,7 +24,7 @@ displaydoc = { workspace = true }
 fixed_decimal = { workspace = true }
 icu_provider = { workspace = true, features = ["macros"] }
 writeable = { workspace = true }
-
+zerovec = { workspace = true }
 databake = { workspace = true, features = ["derive"], optional = true}
 serde = { workspace = true, features = ["derive", "alloc"], optional = true }
 
@@ -46,8 +46,8 @@ criterion = { workspace = true }
 [features]
 default = ["compiled_data"]
 std = ["fixed_decimal/std", "icu_locale_core/std", "icu_provider/std"]
-serde = ["dep:serde", "icu_provider/serde"]
-datagen = ["serde", "dep:databake"]
+serde = ["dep:serde", "icu_provider/serde", "zerovec/serde"]
+datagen = ["serde", "dep:databake", "zerovec/databake"]
 bench = ["serde"]
 compiled_data = ["dep:icu_decimal_data"]
 

components/decimal/benches/fixed_decimal_format.rs

@@ -9,8 +9,10 @@ use rand_pcg::Lcg64Xsh32;
 use criterion::{black_box, criterion_group, criterion_main, Criterion};
 
 use fixed_decimal::FixedDecimal;
-use icu_decimal::provider::DecimalSymbolsV1Marker;
+use icu_decimal::provider::{Baked, DecimalSymbolsV2Marker};
 use icu_decimal::FixedDecimalFormatter;
+use icu_locale_core::locale;
+use icu_provider::prelude::*;
 use icu_provider_adapters::fixed::FixedProvider;
 
 fn triangular_nums(range: f64) -> Vec<isize> {
@@ -26,7 +28,14 @@ fn triangular_nums(range: f64) -> Vec<isize> {
 
 fn overview_bench(c: &mut Criterion) {
     let nums = triangular_nums(1e9);
-    let provider = FixedProvider::<DecimalSymbolsV1Marker>::new_default();
+    let data = Baked
+        .load(DataRequest {
+            id: DataIdentifierBorrowed::for_locale(&locale!("en-US").into()),
+            ..Default::default()
+        })
+        .unwrap()
+        .payload;
+    let provider = FixedProvider::<DecimalSymbolsV2Marker>::from_payload(data);
     c.bench_function("icu_decimal/overview", |b| {
         b.iter(|| {
             // This benchmark demonstrates the performance of the format function on 1000 numbers

components/decimal/src/format.rs

@@ -17,15 +17,16 @@ use writeable::Writeable;
 pub struct FormattedFixedDecimal<'l> {
     pub(crate) value: &'l FixedDecimal,
     pub(crate) options: &'l FixedDecimalFormatterOptions,
-    pub(crate) symbols: &'l DecimalSymbolsV1<'l>,
+    pub(crate) symbols: &'l DecimalSymbolsV2<'l>,
 }
 
 impl FormattedFixedDecimal<'_> {
-    fn get_affixes(&self) -> Option<&AffixesV1> {
+    /// Returns the affixes needed for the current sign, as (prefix, suffix)
+    fn get_affixes(&self) -> Option<(&str, &str)> {
         match self.value.sign() {
             Sign::None => None,
-            Sign::Negative => Some(&self.symbols.minus_sign_affixes),
-            Sign::Positive => Some(&self.symbols.plus_sign_affixes),
+            Sign::Negative => Some(self.symbols.minus_sign_affixes()),
+            Sign::Positive => Some(self.symbols.plus_sign_affixes()),
         }
     }
 }
@@ -37,13 +38,13 @@ impl Writeable for FormattedFixedDecimal<'_> {
     {
         let affixes = self.get_affixes();
         if let Some(affixes) = affixes {
-            sink.write_str(&affixes.prefix)?;
+            sink.write_str(affixes.0)?;
         }
         let range = self.value.magnitude_range();
         let upper_magnitude = *range.end();
         for m in range.rev() {
             if m == -1 {
-                sink.write_str(&self.symbols.decimal_separator)?;
+                sink.write_str(self.symbols.decimal_separator())?;
             }
             #[allow(clippy::indexing_slicing)] // digit_at in 0..=9
             sink.write_char(self.symbols.digits[self.value.digit_at(m) as usize])?;
@@ -53,11 +54,11 @@ impl Writeable for FormattedFixedDecimal<'_> {
                 self.options.grouping_strategy,
                 &self.symbols.grouping_sizes,
             ) {
-                sink.write_str(&self.symbols.grouping_separator)?;
+                sink.write_str(self.symbols.grouping_separator())?;
             }
         }
         if let Some(affixes) = affixes {
-            sink.write_str(&affixes.suffix)?;
+            sink.write_str(affixes.1)?;
         }
         Ok(())
     }

components/decimal/src/grouper.rs

@@ -154,10 +154,10 @@ fn test_grouper() {
     for cas in &cases {
         for i in 0..4 {
             let dec = FixedDecimal::from(1).multiplied_pow10((i as i16) + 3);
-            let provider = FixedProvider::<DecimalSymbolsV1Marker>::from_owned(
-                crate::provider::DecimalSymbolsV1 {
+            let provider = FixedProvider::<DecimalSymbolsV2Marker>::from_owned(
+                crate::provider::DecimalSymbolsV2 {
                     grouping_sizes: cas.sizes,
-                    ..Default::default()
+                    ..DecimalSymbolsV2::new_en_for_testing()
                 },
             );
             let options = options::FixedDecimalFormatterOptions {

components/decimal/src/lib.rs

@@ -104,7 +104,7 @@ use icu_provider::prelude::*;
 use size_test_macro::size_test;
 use writeable::Writeable;
 
-size_test!(FixedDecimalFormatter, fixed_decimal_formatter_size, 208);
+size_test!(FixedDecimalFormatter, fixed_decimal_formatter_size, 88);
 
 /// A formatter for [`FixedDecimal`], rendering decimal digits in an i18n-friendly way.
 ///
@@ -122,7 +122,7 @@ size_test!(FixedDecimalFormatter, fixed_decimal_formatter_size, 208);
 #[derive(Debug)]
 pub struct FixedDecimalFormatter {
     options: options::FixedDecimalFormatterOptions,
-    symbols: DataPayload<provider::DecimalSymbolsV1Marker>,
+    symbols: DataPayload<provider::DecimalSymbolsV2Marker>,
 }
 
 impl AsRef<FixedDecimalFormatter> for FixedDecimalFormatter {
@@ -138,7 +138,7 @@ impl FixedDecimalFormatter {
     );
 
     #[doc = icu_provider::gen_any_buffer_unstable_docs!(UNSTABLE, Self::try_new)]
-    pub fn try_new_unstable<D: DataProvider<provider::DecimalSymbolsV1Marker> + ?Sized>(
+    pub fn try_new_unstable<D: DataProvider<provider::DecimalSymbolsV2Marker> + ?Sized>(
         provider: &D,
         locale: &DataLocale,
         options: options::FixedDecimalFormatterOptions,