boot2

Playing with the boostrap
git clone https://git.ryansepassi.com/git/boot2.git
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081-ubnot-canonical.scm (639B)

      1 ;; tests/cc-cg/81-ubnot-canonical.scm — bitwise-not on unsigned should
      2 ;; leave a canonical 64-bit slot in the to-type's natural form.
      3 ;;
      4 ;; Models:
      5 ;;   unsigned int a = 0;
      6 ;;   return (~a) == 4294967295u;
      7 ;;
      8 ;; Same bug class as 80-uneg-canonical: ~0 in 64-bit is 0xFF..FF,
      9 ;; spilled as u32 without re-canonicalizing causes a literal
     10 ;; 4294967295u (loaded as 0x00000000FFFFFFFF) to compare unequal.
     11 
     12 (let ((cg (cg-init)))
     13   (cg-fn-begin cg "main" '() %t-i32)
     14   (cg-push-imm cg %t-u32 0)
     15   (cg-unop cg 'bnot)
     16   (cg-push-imm cg %t-u32 4294967295)
     17   (cg-binop cg 'eq)
     18   (cg-return cg)
     19   (cg-fn-end cg)
     20   (write-bv-fd 1 (cg-finish cg)))