Auto merge of #84205 - workingjubilee:more-simd-intrin, r=bjorn3

Add simd_{round,trunc} intrinsics

LLVM supports many functions from math.h in its IR. Many of these
have SIMD instructions on various platforms. So, let's add round and
trunc so std::arch can use them.

Yes, exact comparison is intentional: rounding must always return a
valid integer-equal value, except for inf/NAN.

compiler/rustc_codegen_cranelift/src/intrinsics/simd.rs

@@ -277,5 +277,7 @@ pub(super) fn codegen_simd_intrinsic_call<'tcx>(
  // simd_select
  // simd_rem
  // simd_neg
+ // simd_trunc
+ // simd_floor
  }
 }

compiler/rustc_codegen_llvm/src/intrinsic.rs

@@ -1057,8 +1057,10 @@ fn generic_simd_intrinsic(
  sym::simd_fsin => ("sin", bx.type_func(&[vec_ty], vec_ty)),
  sym::simd_fcos => ("cos", bx.type_func(&[vec_ty], vec_ty)),
  sym::simd_fabs => ("fabs", bx.type_func(&[vec_ty], vec_ty)),
- sym::simd_floor => ("floor", bx.type_func(&[vec_ty], vec_ty)),
  sym::simd_ceil => ("ceil", bx.type_func(&[vec_ty], vec_ty)),
+ sym::simd_floor => ("floor", bx.type_func(&[vec_ty], vec_ty)),
+ sym::simd_round => ("round", bx.type_func(&[vec_ty], vec_ty)),
+ sym::simd_trunc => ("trunc", bx.type_func(&[vec_ty], vec_ty)),
  sym::simd_fexp => ("exp", bx.type_func(&[vec_ty], vec_ty)),
  sym::simd_fexp2 => ("exp2", bx.type_func(&[vec_ty], vec_ty)),
  sym::simd_flog10 => ("log10", bx.type_func(&[vec_ty], vec_ty)),
@@ -1083,8 +1085,10 @@ fn generic_simd_intrinsic(
  | sym::simd_fsin
  | sym::simd_fcos
  | sym::simd_fabs
- | sym::simd_floor
  | sym::simd_ceil
+ | sym::simd_floor
+ | sym::simd_round
+ | sym::simd_trunc
  | sym::simd_fexp
  | sym::simd_fexp2
  | sym::simd_flog10

compiler/rustc_span/src/symbol.rs

@@ -1103,6 +1103,7 @@ symbols! {
  simd_reduce_or,
  simd_reduce_xor,
  simd_rem,
+ simd_round,
  simd_saturating_add,
  simd_saturating_sub,
  simd_scatter,
@@ -1111,6 +1112,7 @@ symbols! {
  simd_shl,
  simd_shr,
  simd_sub,
+ simd_trunc,
  simd_xor,
  since,
  sinf32,

compiler/rustc_typeck/src/check/intrinsic.rs

@@ -407,8 +407,8 @@ pub fn check_platform_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>)
  | sym::simd_fpow
  | sym::simd_saturating_add
  | sym::simd_saturating_sub => (1, vec![param(0), param(0)], param(0)),
- sym::simd_neg => (1, vec![param(0)], param(0)),
- sym::simd_fsqrt
+ sym::simd_neg
+ | sym::simd_fsqrt
  | sym::simd_fsin
  | sym::simd_fcos
  | sym::simd_fexp
@@ -417,8 +417,10 @@ pub fn check_platform_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>)
  | sym::simd_flog10
  | sym::simd_flog
  | sym::simd_fabs
+ | sym::simd_ceil
  | sym::simd_floor
- | sym::simd_ceil => (1, vec![param(0)], param(0)),
+ | sym::simd_round
+ | sym::simd_trunc => (1, vec![param(0)], param(0)),
  sym::simd_fpowi => (1, vec![param(0), tcx.types.i32], param(0)),
  sym::simd_fma => (1, vec![param(0), param(0), param(0)], param(0)),
  sym::simd_gather => (3, vec![param(0), param(1), param(2)], param(0)),

src/test/ui/simd/simd-intrinsic-float-math.rs

@@ -20,16 +20,20 @@ extern "platform-intrinsic" {
  fn simd_fabs<T>(x: T) -> T;
  fn simd_fsin<T>(x: T) -> T;
  fn simd_fcos<T>(x: T) -> T;
- fn simd_ceil<T>(x: T) -> T;
  fn simd_fexp<T>(x: T) -> T;
  fn simd_fexp2<T>(x: T) -> T;
- fn simd_floor<T>(x: T) -> T;
  fn simd_fma<T>(x: T, y: T, z: T) -> T;
  fn simd_flog<T>(x: T) -> T;
  fn simd_flog10<T>(x: T) -> T;
  fn simd_flog2<T>(x: T) -> T;
  fn simd_fpow<T>(x: T, y: T) -> T;
  fn simd_fpowi<T>(x: T, y: i32) -> T;
+
+ // rounding functions
+ fn simd_ceil<T>(x: T) -> T;
+ fn simd_floor<T>(x: T) -> T;
+ fn simd_round<T>(x: T) -> T;
+ fn simd_trunc<T>(x: T) -> T;
 }
 
 macro_rules! assert_approx_eq_f32 {
@@ -64,18 +68,12 @@ fn main() {
  let r = simd_fcos(z);
  assert_approx_eq!(x, r);
 
- let r = simd_ceil(h);
- assert_approx_eq!(x, r);
-
  let r = simd_fexp(z);
  assert_approx_eq!(x, r);
 
  let r = simd_fexp2(z);
  assert_approx_eq!(x, r);
 
- let r = simd_floor(h);
- assert_approx_eq!(z, r);
-
  let r = simd_fma(x, h, h);
  assert_approx_eq!(x, r);
 
@@ -99,5 +97,18 @@ fn main() {
 
  let r = simd_fsin(z);
  assert_approx_eq!(z, r);
+
+ // rounding functions
+ let r = simd_floor(h);
+ assert_eq!(z, r);
+
+ let r = simd_ceil(h);
+ assert_eq!(x, r);
+
+ let r = simd_round(h);
+ assert_eq!(x, r);
+
+ let r = simd_trunc(h);
+ assert_eq!(z, r);
  }
 }