From f53fb153b6234dc8d6fe112a289a731f22456752 Mon Sep 17 00:00:00 2001
From: Christian Guinard <28689358+christiangnrd@users.noreply.github.com>
Date: Wed, 5 Mar 2025 15:00:37 -0400
Subject: [PATCH 1/5] Improve test coverage

---
 test/mathfuncs.jl |  3 +++
 test/runtests.jl  | 61 ++++++++++++++++++++++++++++++++++++++++++++---
 test/structure.jl | 15 ++++++------
 3 files changed, 69 insertions(+), 10 deletions(-)

diff --git a/test/mathfuncs.jl b/test/mathfuncs.jl
index 1d57b32..ac76132 100644
--- a/test/mathfuncs.jl
+++ b/test/mathfuncs.jl
@@ -19,3 +19,6 @@ for F in (:asec, :acsc, :cosh, :acosh, :acoth)
   end
 end
 
+
+x,y = rand(Float32, 2)
+@test widemul(BFloat16(x), BFloat16(y)) isa Float32
diff --git a/test/runtests.jl b/test/runtests.jl
index 58a9ef7..6579f5a 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -2,6 +2,18 @@ using Test, BFloat16s, Printf, Random
 
 @info "Testing BFloat16s" BFloat16s.llvm_storage BFloat16s.llvm_arithmetic
 
+@testset "BFloat16s" begin
+
+@testset "basics" begin
+    @test Base.exponent_bits(BFloat16) == 8
+    @test Base.significand_bits(BFloat16) == 7
+    @test precision(BFloat16) == 8
+    @test Base.uinttype(BFloat16) == UInt16
+
+    @test typemin(BFloat16) == -BFloat16s.InfB16
+    @test typemax(BFloat16) == BFloat16s.InfB16
+end
+
 @testset "comparisons" begin
     @test BFloat16(1)   <  BFloat16(2)
     @test BFloat16(1f0) <  BFloat16(2f0)
@@ -18,17 +30,46 @@ using Test, BFloat16s, Printf, Random
     @test BFloat16(2)   != BFloat16(1)
     @test BFloat16(2f0) != BFloat16(1f0)
     @test BFloat16(2.0) != BFloat16(1.0)
+    @test BFloat16(NaN) != BFloat16(1.0)
+    @test !(BFloat16(1.0) == BFloat16(NaN))
     @test iszero(BFloat16(0)) == true
     @test iszero(BFloat16(3.45)) == false
 end
 
+@testset "trunc" begin
+    bf_val = BFloat16(5.5)
+    @testset "$Ti" for Ti in (Int8, Int16, Int32, Int64, Int128, UInt8, UInt16, UInt32, UInt64, UInt128)
+        if !(BFloat16s.llvm_arithmetic && sizeof(Ti) == 16) # Can't use skip  argument in @test on 1.6
+            @test trunc(Ti, bf_val) == Ti(5)
+        else
+            @test_skip trunc(Ti, bf_val) == Ti(5)
+        end
+    end
+
+    @test trunc(BFloat16, Float32(π)) == BFloat16(3.140625)
+
+    #InexactError
+    @test_throws InexactError trunc(Int16, typemax(BFloat16))
+    @test_throws InexactError trunc(UInt16, typemax(BFloat16))
+end
+
 @testset "conversions" begin
     @test Float32(BFloat16(10)) == 1f1
     @test Float64(BFloat16(10)) == 10.0
     @test Int32(BFloat16(10)) == Int32(10)
+    @test UInt32(BFloat16(10)) == Int32(10)
     @test Int64(BFloat16(10)) == Int64(10)
+    @test UInt64(BFloat16(10)) == Int64(10)
     @test BFloat16(BigFloat(1)) == BFloat16(1)
     @test BigFloat(BFloat16(1)) == BigFloat(1)
+    @test Float16(BFloat16(3.140625)) == Float16(π)
+    @test BFloat16(Float16(π)) == BFloat16(3.140625)
+
+    @test promote(BFloat16(4.5), Float64(5.0)) == (Float64(4.5), Float64(5.0))
+    @test promote(BFloat16(4.5), Float32(5.0)) == (Float32(4.5), Float32(5.0))
+
+    @test_throws InexactError Int16(typemax(BFloat16))
+    @test_throws InexactError UInt16(typemax(BFloat16))
 end
 
 @testset "abi" begin
@@ -44,6 +85,8 @@ end
     @test BFloat16(2) ^ BFloat16(4) == BFloat16(16)
     @test eps(BFloat16) == BFloat16(0.0078125)
     @test sqrt(BFloat16(4f0)) == BFloat16(2f0)
+    @test rem(BFloat16(3.14), Int) == 3
+    @test round(BFloat16(10.4), RoundToZero) == BFloat16(10.0)
     @test round(BFloat16(10.4), RoundUp) == BFloat16(11.0)
     @test round(BFloat16(10.6), RoundDown) == BFloat16(10.0)
     @test round(BFloat16(3.2), RoundNearest) == BFloat16(3.0)
@@ -92,6 +135,13 @@ end
     @test (@sprintf "%a" BFloat16(1.5)) == "0x1.8p+0"
 end
 
+@testset "show" begin
+    @test repr(BFloat16(Inf)) == "InfB16"
+    @test repr(BFloat16(-Inf)) == "-InfB16"
+    @test repr(BFloat16(NaN)) == "NaNB16"
+    @test repr(BFloat16(2)) == "BFloat16(2.0)"
+end
+
 @testset "random" begin
   x = Array{BFloat16}(undef, 10)
   y = Array{BFloat16}(undef, 10)
@@ -134,6 +184,9 @@ end
 
     @test x < nextfloat(x)
     @test x > prevfloat(x)
+
+    @test nextfloat(x, typemax(Int)) == typemax(BFloat16)
+    @test prevfloat(x, typemax(Int)) == typemin(BFloat16)
   end
 
   @test isnan(nextfloat(BFloat16s.NaNB16))
@@ -171,7 +224,7 @@ end
 end
 
 @testset "maxintfloat" begin
-  
+
   a = maxintfloat(BFloat16)
   @test a+1-1 == a-1    # the first +1 cannot be represented
   @test a-1+1 == a      # but -1 can
@@ -180,7 +233,7 @@ end
 @testset "rand sampling" begin
   Random.seed!(123)
   mi, ma = extrema(rand(BFloat16, 1_000_000))
-  
+
   # zero should be the lowest BFloat16 sampled
   @test mi === zero(BFloat16)
 
@@ -189,4 +242,6 @@ end
 end
 
 include("structure.jl")
-include("mathfuncs.jl")
\ No newline at end of file
+include("mathfuncs.jl")
+
+end # @testset "BFloat16s"
diff --git a/test/structure.jl b/test/structure.jl
index 81eb0e1..a9dac48 100644
--- a/test/structure.jl
+++ b/test/structure.jl
@@ -12,25 +12,26 @@ uint(x::BFloat16) = reinterpret(UInt16, x)
 @testset "BFloat16 bits" begin
   @test uint(two) == 0x4000
   @test uint(half) == 0x3f00
+  @test bitstring(two) == "0100000000000000"
+  @test bitstring(half) == "0011111100000000"
   @test signbit(two) == false
 end
 
 @testset "BFloat16 parts" begin
   @test exponent(whole) == 0
   @test significand(whole) == one(BFloat16)
-  
+
+  # subnormal
+  @test significand(reinterpret(BFloat16, 0b0000000000000001)) == one(BFloat16)
+
   @test frexp(phi) == (BFloat16(0.80859375), 1)
   @test ldexp(BFloat16(0.80859375), 1) == phi
-  
+
   @test exponent(invphi3) == -3
   @test significand(invphi3) == BFloat16(1.8828125)
-  
+
   fr,xp = frexp(invphi3)
   @test xp == -2
   @test fr == BFloat16(0.94140625)
   @test ldexp(fr, xp) == invphi3
 end
-
-
-  
-    

From c557bc8cf83943df18dbcf6a1c7515f055f3d672 Mon Sep 17 00:00:00 2001
From: Christian Guinard <28689358+christiangnrd@users.noreply.github.com>
Date: Wed, 5 Mar 2025 19:33:38 -0400
Subject: [PATCH 2/5] Add Codecov badge

---
 README.md | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 1177cce..f6c6560 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,9 @@
 # BFloat16s.jl
-[![MIT license](http://img.shields.io/badge/license-MIT-brightgreen.svg)](http://opensource.org/licenses/MIT) 
+[![MIT license](http://img.shields.io/badge/license-MIT-brightgreen.svg)](http://opensource.org/licenses/MIT)
+[codecov-img]][codecov-url]
+
+[codecov-img]: https://codecov.io/gh/JuliaMath/BFloat16s.jl/branch/master/graph/badge.svg
+[codecov-url]: https://codecov.io/gh/JuliaMath/BFloat16s.jl
 
 This package defines the [BFloat16 data type](https://en.wikipedia.org/wiki/Bfloat16_floating-point_format),
 a floating-point format with 1 sign bit, 8 exponent bits and 7 mantissa bits.

From c4ce9089670746866898c7bca16ed658e18193fc Mon Sep 17 00:00:00 2001
From: Christian Guinard <28689358+christiangnrd@users.noreply.github.com>
Date: Wed, 5 Mar 2025 19:53:05 -0400
Subject: [PATCH 3/5] LowPrecArray tests

---
 test/lowprecarrays.jl | 25 +++++++++++++++++++++++++
 test/runtests.jl      |  1 +
 2 files changed, 26 insertions(+)
 create mode 100644 test/lowprecarrays.jl

diff --git a/test/lowprecarrays.jl b/test/lowprecarrays.jl
new file mode 100644
index 0000000..afa3854
--- /dev/null
+++ b/test/lowprecarrays.jl
@@ -0,0 +1,25 @@
+@testset "lowprecarrays" begin
+    A = rand(Float32, 10,10)
+    lpA = LowPrecArray(A)
+
+    @test lpA isa LowPrecArray
+    @test size(A) == size(lpA)
+
+   lpA[3] = 4
+    @test lpA[3] == A[3]
+
+    a = rand(Float32)
+    ab = BFloat16s.ExpandingBFloat16(a)
+    b = rand(Float32)
+    bb = BFloat16s.ExpandingBFloat16(b)
+
+    @test ab isa BFloat16s.ExpandingBFloat16
+    @test ab.a isa BFloat16
+    @test ab * bb isa Float32
+
+    B = LowPrecArray(rand(Float32, 10,10))
+    C = LowPrecArray(rand(Float32, 10,10))
+
+    lpA .= B*C
+
+end # @testset "lowprecarrays"
\ No newline at end of file
diff --git a/test/runtests.jl b/test/runtests.jl
index 6579f5a..a97e714 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -243,5 +243,6 @@ end
 
 include("structure.jl")
 include("mathfuncs.jl")
+include("lowprecarrays.jl")
 
 end # @testset "BFloat16s"

From 8dc1905316c9433de9cb5b551bdcb5bca6fda654 Mon Sep 17 00:00:00 2001
From: Christian Guinard <28689358+christiangnrd@users.noreply.github.com>
Date: Fri, 7 Mar 2025 10:15:24 -0400
Subject: [PATCH 4/5] whitespace

---
 test/lowprecarrays.jl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/lowprecarrays.jl b/test/lowprecarrays.jl
index afa3854..e7d4b41 100644
--- a/test/lowprecarrays.jl
+++ b/test/lowprecarrays.jl
@@ -22,4 +22,4 @@
 
     lpA .= B*C
 
-end # @testset "lowprecarrays"
\ No newline at end of file
+end # @testset "lowprecarrays"

From aa7edcfac648eb2211bc5c710a962ff9867badd5 Mon Sep 17 00:00:00 2001
From: Christian Guinard <28689358+christiangnrd@users.noreply.github.com>
Date: Fri, 7 Mar 2025 14:39:46 -0400
Subject: [PATCH 5/5] Define `Base.issubnormal(x:BFloat16)`

---
 src/bfloat16.jl   |  5 +++++
 test/structure.jl | 11 +++++++++--
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/src/bfloat16.jl b/src/bfloat16.jl
index ef95afe..e53d6bb 100644
--- a/src/bfloat16.jl
+++ b/src/bfloat16.jl
@@ -63,6 +63,11 @@ Base.exponent_bits(::Type{BFloat16}) = 8
 Base.significand_bits(::Type{BFloat16}) = 7
 Base.signbit(x::BFloat16) = (reinterpret(Unsigned, x) & 0x8000) !== 0x0000
 
+function Base.issubnormal(x::BFloat16)
+    y = reinterpret(Unsigned, x)
+    return (y & exponent_mask(BFloat16) == 0) & (y & significand_mask(BFloat16) != 0)
+end
+
 function Base.significand(x::BFloat16)
     xu = reinterpret(Unsigned, x)
     xs = xu & ~sign_mask(BFloat16)
diff --git a/test/structure.jl b/test/structure.jl
index a9dac48..63e6f16 100644
--- a/test/structure.jl
+++ b/test/structure.jl
@@ -22,8 +22,15 @@ end
   @test significand(whole) == one(BFloat16)
 
   # subnormal
-  @test significand(reinterpret(BFloat16, 0b0000000000000001)) == one(BFloat16)
-
+  @testset "subnormal" begin
+      allbfs = UInt16(1):typemax(UInt16)
+      res = map(allbfs) do raw
+          bf = reinterpret(BFloat16, raw)
+          issubnormal(bf) == issubnormal(Float32(bf))
+      end
+      @test all(res)
+      @test significand(reinterpret(BFloat16, 0b0000000000000001)) == one(BFloat16)
+  end
   @test frexp(phi) == (BFloat16(0.80859375), 1)
   @test ldexp(BFloat16(0.80859375), 1) == phi