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core: Implement non-trivial builtin functions using IRRT

This commit is contained in:
David Mak 2023-11-06 12:57:23 +08:00
parent c2ab6b58ff
commit 08a5050f9a
3 changed files with 129 additions and 159 deletions

View File

@ -145,4 +145,55 @@ int32_t __nac3_isinf(double x) {
int32_t __nac3_isnan(double x) {
return __builtin_isnan(x);
}
double tgamma(double arg);
double __nac3_gamma(double z) {
// Handling for denormals
// | x | Python gamma(x) | C tgamma(x) |
// --- | ----------------- | --------------- | ----------- |
// (1) | nan | nan | nan |
// (2) | -inf | -inf | inf |
// (3) | inf | inf | inf |
// (4) | 0.0 | inf | inf |
// (5) | {-1.0, -2.0, ...} | inf | nan |
// (1)-(3)
if (__builtin_isinf(z) || __builtin_isnan(z)) {
return z;
}
double v = tgamma(z);
// (4)-(5)
return __builtin_isinf(v) || __builtin_isnan(v) ? __builtin_inf() : v;
}
double lgamma(double arg);
double __nac3_gammaln(double x) {
// libm's handling of value overflows differs from scipy:
// - scipy: gammaln(-inf) -> -inf
// - libm : lgamma(-inf) -> inf
if (__builtin_isinf(x)) {
return x;
}
return lgamma(x);
}
double j0(double x);
double __nac3_j0(double x) {
// libm's handling of value overflows differs from scipy:
// - scipy: j0(inf) -> nan
// - libm : j0(inf) -> 0.0
if (__builtin_isinf(x)) {
return __builtin_nan("");
}
return j0(x);
}

View File

@ -472,3 +472,60 @@ pub fn call_isnan<'ctx, 'a>(
generator.bool_to_i1(ctx, ret)
}
/// Generates a call to `gamma` in IR. Returns an `f64` representing the result.
pub fn call_gamma<'ctx, 'a>(
ctx: &CodeGenContext<'ctx, 'a>,
v: FloatValue<'ctx>,
) -> FloatValue<'ctx> {
let llvm_f64 = ctx.ctx.f64_type();
let intrinsic_fn = ctx.module.get_function("__nac3_gamma").unwrap_or_else(|| {
let fn_type = llvm_f64.fn_type(&[llvm_f64.into()], false);
ctx.module.add_function("__nac3_gamma", fn_type, None)
});
ctx.builder
.build_call(intrinsic_fn, &[v.into()], "gamma")
.try_as_basic_value()
.unwrap_left()
.into_float_value()
}
/// Generates a call to `gammaln` in IR. Returns an `f64` representing the result.
pub fn call_gammaln<'ctx, 'a>(
ctx: &CodeGenContext<'ctx, 'a>,
v: FloatValue<'ctx>,
) -> FloatValue<'ctx> {
let llvm_f64 = ctx.ctx.f64_type();
let intrinsic_fn = ctx.module.get_function("__nac3_gammaln").unwrap_or_else(|| {
let fn_type = llvm_f64.fn_type(&[llvm_f64.into()], false);
ctx.module.add_function("__nac3_gammaln", fn_type, None)
});
ctx.builder
.build_call(intrinsic_fn, &[v.into()], "gammaln")
.try_as_basic_value()
.unwrap_left()
.into_float_value()
}
/// Generates a call to `j0` in IR. Returns an `f64` representing the result.
pub fn call_j0<'ctx, 'a>(
ctx: &CodeGenContext<'ctx, 'a>,
v: FloatValue<'ctx>,
) -> FloatValue<'ctx> {
let llvm_f64 = ctx.ctx.f64_type();
let intrinsic_fn = ctx.module.get_function("__nac3_j0").unwrap_or_else(|| {
let fn_type = llvm_f64.fn_type(&[llvm_f64.into()], false);
ctx.module.add_function("__nac3_j0", fn_type, None)
});
ctx.builder
.build_call(intrinsic_fn, &[v.into()], "j0")
.try_as_basic_value()
.unwrap_left()
.into_float_value()
}

View File

@ -2,7 +2,14 @@ use super::*;
use crate::{
codegen::{
expr::destructure_range,
irrt::{calculate_len_for_slice_range, call_isinf, call_isnan},
irrt::{
calculate_len_for_slice_range,
call_gamma,
call_gammaln,
call_isinf,
call_isnan,
call_j0,
},
stmt::exn_constructor,
},
symbol_resolver::SymbolValue,
@ -1675,7 +1682,6 @@ pub fn get_builtins(primitives: &mut (PrimitiveStore, Unifier)) -> BuiltinInfo {
&[(float, "z")],
Box::new(|ctx, _, fun, args, generator| {
let float = ctx.primitives.float;
let llvm_f64 = ctx.ctx.f64_type();
let z_ty = fun.0.args[0].ty;
let z_val = args[0].1.clone()
@ -1683,77 +1689,9 @@ pub fn get_builtins(primitives: &mut (PrimitiveStore, Unifier)) -> BuiltinInfo {
assert!(ctx.unifier.unioned(z_ty, float));
let tgamma_fn = ctx.module.get_function("tgamma").unwrap_or_else(|| {
let fn_type = llvm_f64.fn_type(&[llvm_f64.into()], false);
let func = ctx.module.add_function("tgamma", fn_type, None);
func.add_attribute(
AttributeLoc::Function,
ctx.ctx.create_enum_attribute(Attribute::get_named_enum_kind_id("nounwind"), 0)
);
func
});
// %0 = call f64 @tgamma(f64 %z)
let call = ctx.builder
.build_call(tgamma_fn, &[z_val.into()], "gamma")
.try_as_basic_value()
.left()
.unwrap()
.into_float_value();
// Handling for denormals
// | x | Python gamma(x) | C tgamma(x) |
// --- | ----------------- | --------------- | ----------- |
// (1) | nan | nan | nan |
// (2) | -inf | -inf | inf |
// (3) | inf | inf | inf |
// (4) | 0.0 | inf | inf |
// (5) | {-1.0, -2.0, ...} | inf | nan |
//
// Therefore, we remap to Python's denorm handling by:
//
// let v = tgamma(x);
// v = if isinf(v) || isnan(v) { f64::INFINITY } else { v } // Handles (4)-(5)
// v = if isinf(x) || isnan(x) { x } else { v } // Handles (1)-(3)
// %v.isinf = call i32 @__nac3_isinf(f64 %0)
// %v.isinf.tobool = icmp ne i32 %v.isinf, 0
let v_isinf = call_isinf(generator, ctx, call.into());
// %v.isnan = call i32 @__nac3_isnan(f64 %0)
// %v.isnan.tobool = icmp ne i32 %v.isnan, 0
let v_isnan = call_isnan(generator, ctx, call.into());
// %or = or i1 %v.isinf.tobool, %v.isnan.tobool
// %3 = select i1 %or, f64 inf, f64 %0
let v_is_nonnum = ctx.builder.build_or(v_isinf, v_isnan, "");
let val = ctx.builder.build_select(
v_is_nonnum,
llvm_f64.const_float(f64::INFINITY).into(),
call,
"",
).into_float_value();
// %z.isinf = call i32 @__nac3_isinf(f64 %z)
// %z.isinf.tobool = icmp ne i32 %z.isinf, 0
let z_isinf = call_isinf(generator, ctx, z_val.into_float_value());
// %z.isnan = call i32 @__nac3_isnan(f64 %z)
// %z.isnan.tobool = icmp ne i32 %z.isnan, 0
let z_isnan = call_isnan(generator, ctx, z_val.into_float_value());
// %or = or i1 %z.isinf.tobool, %z.isnan.tobool
// %val = select i1 %or, f64 %z, f64 %3
let z_is_nonnum = ctx.builder.build_or(z_isinf, z_isnan, "");
let val = ctx.builder.build_select(
z_is_nonnum,
z_val.into_float_value(),
val,
"",
);
Ok(val.into())
}),
),
Ok(Some(call_gamma(ctx, z_val.into_float_value()).into()))
}
)),
create_fn_by_codegen(
primitives,
&var_map,
@ -1762,53 +1700,14 @@ pub fn get_builtins(primitives: &mut (PrimitiveStore, Unifier)) -> BuiltinInfo {
&[(float, "x")],
Box::new(|ctx, _, fun, args, generator| {
let float = ctx.primitives.float;
let llvm_f64 = ctx.ctx.f64_type();
let x_ty = fun.0.args[0].ty;
let x_val = args[0].1.clone()
.to_basic_value_enum(ctx, generator, x_ty)?;
let z_ty = fun.0.args[0].ty;
let z_val = args[0].1.clone()
.to_basic_value_enum(ctx, generator, z_ty)?;
assert!(ctx.unifier.unioned(x_ty, float));
assert!(ctx.unifier.unioned(z_ty, float));
let tgamma_fn = ctx.module.get_function("lgamma").unwrap_or_else(|| {
let fn_type = llvm_f64.fn_type(&[llvm_f64.into()], false);
let func = ctx.module.add_function("lgamma", fn_type, None);
func.add_attribute(
AttributeLoc::Function,
ctx.ctx.create_enum_attribute(Attribute::get_named_enum_kind_id("nounwind"), 0)
);
func
});
// %0 = call f64 @gamma(f64 %x)
let call = ctx.builder
.build_call(tgamma_fn, &[x_val.into()], "gammaln")
.try_as_basic_value()
.left()
.unwrap()
.into_float_value();
// libm's handling of value overflows differs from scipy:
// - scipy: gammaln(-inf) -> -inf
// - libm : lgamma(-inf) -> inf
//
// Therefore we remap it by:
//
// let v = lgamma(x);
// v = if isinf(x) { x } else { v }
// %isinf = call i32 @__nac3_isinf(f64 %x)
// %tobool = icmp ne i32 %isinf, 0
// %val = select i1 %tobool, f64 %x, f64 %0
let v = ctx.builder.build_select(
call_isinf(generator, ctx, x_val.into_float_value()),
x_val,
call.into(),
""
);
Ok(v.into())
Ok(Some(call_gammaln(ctx, z_val.into_float_value()).into()))
}),
),
create_fn_by_codegen(
@ -1819,51 +1718,14 @@ pub fn get_builtins(primitives: &mut (PrimitiveStore, Unifier)) -> BuiltinInfo {
&[(float, "x")],
Box::new(|ctx, _, fun, args, generator| {
let float = ctx.primitives.float;
let llvm_f64 = ctx.ctx.f64_type();
let x_ty = fun.0.args[0].ty;
let x_val = args[0].1.clone()
.to_basic_value_enum(ctx, generator, x_ty)?;
let z_ty = fun.0.args[0].ty;
let z_val = args[0].1.clone()
.to_basic_value_enum(ctx, generator, z_ty)?;
assert!(ctx.unifier.unioned(x_ty, float));
assert!(ctx.unifier.unioned(z_ty, float));
let tgamma_fn = ctx.module.get_function("j0").unwrap_or_else(|| {
let fn_type = llvm_f64.fn_type(&[llvm_f64.into()], false);
let func = ctx.module.add_function("j0", fn_type, None);
func.add_attribute(
AttributeLoc::Function,
ctx.ctx.create_enum_attribute(Attribute::get_named_enum_kind_id("nounwind"), 0)
);
func
});
// %0 = call f64 @j0(f64 %x)
let call = ctx.builder
.build_call(tgamma_fn, &[x_val.into()], "j0")
.try_as_basic_value()
.left()
.unwrap()
.into_float_value();
// libm's handling of value overflows differs from scipy:
// - scipy: j0(inf) -> nan
// - libm : j0(inf) -> 0.0
//
// Therefore we remap it by:
//
// let v = j0(x);
// v = if isinf(x) { f64::NAN } else { v }
// %1 = call i32 @__nac3_isinf(f64 %x)
// %tobool = icmp ne i32 %isinf, 0
let arg_isinf = call_isinf(generator, ctx, x_val.into_float_value());
// %val = select i1 %tobool, f64 nan, f64 %0
let val = ctx.builder
.build_select(arg_isinf, llvm_f64.const_float(f64::NAN), call, "");
Ok(val.into())
Ok(Some(call_j0(ctx, z_val.into_float_value()).into()))
}),
),
create_fn_by_extern(