Fast exit for Grade with 2 or fewer elements; always enable counting sort otherwise

1 files changed, 24 insertions, 24 deletions

diff --git a/src/r.bqn b/src/r.bqn
index c41d48e7..e35564f8 100644
--- a/src/r.bqn
+++ b/src/r.bqn
@@ -140,32 +140,32 @@ Cmp ← +○IsArray◶⟨
 
 _grade ← {
   gt ← 𝕗
-  cmps ← {𝕏˜}⌜⍟𝕗⟨≤,Cmp≤0˙,Cmp0,Cmp⟩
-  GetLE ← {
-    m←1-1=𝕨 ⋄ a←0<0+´IsArray⌜𝕩
-    𝕨 {(𝕏 _getCellCmp 𝕨)≤0˙}⍟m 𝕩{𝕏○(⊑⟜𝕗)} (a+2×m)⊑cmps
-  }
-  {
+  cmps ← {𝕏˜}⌜⍟𝕗⟨Cmp,Cmp0,Cmp≤0˙,≤⟩
+  0 Fill {
     "⍋𝕩: 𝕩 must have rank at least 1" ! 1≤=𝕩
     l←≠𝕩
-    m←1×´1 Cell 𝕩
-    𝕩↩⥊𝕩
-    Merge ← { # Merge sort
-      le←m GetLE 𝕩
-      B←l⊸≤◶⊢‿l
-      (↕l){
-        i←-d←𝕨 ⋄ j←ei←ej←0
-        e←3 ⋄ G←LE○(⊑⟜(m⊸×⌜⍟(1-m=1)𝕩)) ⋄ c←⟨1-G,0,1,2⟩
-        s←(8≤d)⊑⟨+,{(𝕩-1){𝕩⋄e↩2⋄j↩i⋄i↩𝕩}⍟G⍟(1-e)𝕩}⟩
-        N←{i↩d+𝕨⋄ej↩B d+ei↩B j↩d+𝕩⋄e↩l≤j⋄S ei⋄i R j}
-        R←{𝕨e◶c𝕩}◶{e+↩2×ei=i↩1+𝕨⋄𝕨}‿{e+↩ej=j↩1+𝕩⋄𝕩}‿N
-        {(i R j)⊑𝕩}⟜𝕩⌜𝕩
-      }´(2⋆ni-1+⊢)⌜↕ni←⌈2 Log l+l=0
-    }
-    # Counting sort for small-range ints
-    bl←bu←0 ⋄ Count←{GroupLen⊸GroupOrd (gt⊑⟨-⟜bl,bu⊸-⟩)⌜𝕩}
-    sr←{((bu↩⌈´𝕩)-bl↩⌊´𝕩)≤2×l}∘𝕩⍟⊢((m=1)×32<l)◶0‿(1×´Int⌜)𝕩
-    0 Fill sr◶Merge‿Count 𝕩
+    (2≤l)◶⟨↕∘l,{
+      m1←1=m←1×´1 Cell 𝕩
+      𝕩↩⥊𝕩
+      a0←1⋄ts←0⋄{a0×↩1≤𝕩⋄ts+↩𝕩}∘Type⌜𝕩
+      cs←a0+2×m1
+      Merge ← { # Merge sort
+        le ← m {(𝕏 _getCellCmp m)≤0˙}⍟(1-m1) 𝕩{𝕏○(⊑⟜𝕗)} cs⊑cmps
+        B←l⊸≤◶⊢‿l
+        (↕l){
+          i←-d←𝕨 ⋄ j←ei←ej←0
+          e←3 ⋄ G←LE○(⊑⟜(m⊸×⌜⍟(1-m=1)𝕩)) ⋄ c←⟨1-G,0,1,2⟩
+          s←(8≤d)⊑⟨+,{(𝕩-1){𝕩⋄e↩2⋄j↩i⋄i↩𝕩}⍟G⍟(1-e)𝕩}⟩
+          N←{i↩d+𝕨⋄ej↩B d+ei↩B j↩d+𝕩⋄e↩l≤j⋄S ei⋄i R j}
+          R←{𝕨e◶c𝕩}◶{e+↩2×ei=i↩1+𝕨⋄𝕨}‿{e+↩ej=j↩1+𝕩⋄𝕩}‿N
+          {(i R j)⊑𝕩}⟜𝕩⌜𝕩
+        }´(2⋆ni-1+⊢)⌜↕ni←⌈2 Log l+l=0
+      }
+      # Counting sort for small-range ints
+      bl←bu←0 ⋄ Count←{GroupLen⊸GroupOrd (gt⊑⟨-⟜bl,bu⊸-⟩)⌜𝕩}
+      sr←((3=cs)×ts=l)◶⟨0,(1×´⌊⊸=⌜)◶0‿{((bu↩⌈´𝕩)-bl↩⌊´𝕩)≤2×l}⟩𝕩
+      sr◶Merge‿Count 𝕩
+    }⟩𝕩
   }
 }
 _binSearch ← {