Add optimizations for urem

Author: KGrewal1

cranelift/codegen/src/opts/cprop.isle

@@ -47,6 +47,12 @@
       (if-let d (u64_checked_div k1 k2))
       (iconst ty (imm64_masked ty d)))
 
+(rule (simplify_skeleton
+       (urem (iconst_u ty k1)
+             (iconst_u ty k2)))
+      (if-let d (u64_checked_rem k1 k2))
+      (iconst ty (imm64_masked ty d)))
+
 (rule (simplify
        (bor (fits_in_64 ty)
             (iconst ty (u64_from_imm64 k1))

cranelift/filetests/filetests/egraph/skeleton.clif

@@ -95,6 +95,21 @@ block0:
 ;     return v18  ; v18 = 1
 ; }
 
+function %cprop_urem() -> i32 {
+block0:
+    v0 = iconst.i32 13
+    v1 = iconst.i32 7
+    v2 = urem v0, v1
+    return v2
+}
+
+; function %cprop_urem() -> i32 fast {
+; block0:
+;     v37 = iconst.i32 6
+;     v2 -> v37
+;     return v37  ; v37 = 6
+; }
+
 function %cprop_sdiv() -> i32 {
 block0:
     v0 = iconst.i32 -7