Pi and e to Float32 and Float16 (#559)

* pi and e to Float32 and Float16

* Mimic Julia behaviour

* Fix

* OOPS

* Automated definitions

Author: christiangnrd

src/device/intrinsics/math.jl

@@ -2,12 +2,19 @@
 
 using Base: FastMath
 using Base.Math: throw_complex_domainerror
+import Core: Float16, Float32
 
 # TODO:
 # - wrap all intrinsics from include/metal/metal_math
 # - add support for vector types
 # - consider emitting LLVM intrinsics and lowering those in the back-end
 
+### Constants
+# π and ℯ
+for T in (:Float16,:Float32), R in (RoundUp, RoundDown), irr in (π, ℯ)
+    @eval @device_override $T(::typeof($irr), ::typeof($R)) = $@eval($T($irr,$R))
+end
+
 ### Common Intrinsics
 @device_function clamp_fast(x::Float32, minval::Float32, maxval::Float32) = ccall("extern air.fast_clamp.f32", llvmcall, Cfloat, (Cfloat, Cfloat, Cfloat), x, minval, maxval)
 @device_override Base.clamp(x::Float32, minval::Float32, maxval::Float32) = ccall("extern air.clamp.f32", llvmcall, Cfloat, (Cfloat, Cfloat, Cfloat), x, minval, maxval)

test/device/intrinsics/math.jl

@@ -311,6 +311,21 @@ end
         ir = sprint(io->(@device_code_llvm io=io dump_module=true @metal metal = v"3.0" nextafter_out_test()))
         @test occursin(Regex("@air\\.sign\\.f$(8*sizeof(T))"), ir)
     end
+
+    # Borrowed from the Julia "Irrationals compared with Rationals and Floats" testset
+    @testset "Comparisons with $irr" for irr in (π, ℯ)
+        @eval function convert_test(res)
+            res[1] = $T($irr, RoundDown) < $irr
+            res[2] = $T($irr, RoundUp) > $irr
+            res[3] = !($T($irr, RoundDown) > $irr)
+            res[4] = !($T($irr, RoundUp) < $irr)
+            return nothing
+        end
+
+        res = MtlArray(zeros(Bool, 4))
+        Metal.@sync @metal convert_test(res)
+        @test all(Array(res))
+    end
 end
 end