boot2

Playing with the boostrap
git clone https://git.ryansepassi.com/git/boot2.git
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082-uadd-wrap-canonical.scm (648B)

      1 ;; tests/cc-cg/82-uadd-wrap-canonical.scm — unsigned add must wrap
      2 ;; correctly into the canonical 64-bit slot form.
      3 ;;
      4 ;; Models:
      5 ;;   unsigned int a = 4294967295u;
      6 ;;   return (a + 1u) == 0u;
      7 ;;
      8 ;; Bug: cg-binop add computes 0xFFFFFFFF + 1 = 0x100000000 in 64-bit.
      9 ;; Spilled as u32 without zero-extending the low 32 bits, the result
     10 ;; compares unequal to 0u (which loads as 0x0).
     11 
     12 (let ((cg (cg-init)))
     13   (cg-fn-begin cg "main" '() %t-i32)
     14   (cg-push-imm cg %t-u32 4294967295)
     15   (cg-push-imm cg %t-u32 1)
     16   (cg-binop cg 'add)
     17   (cg-push-imm cg %t-u32 0)
     18   (cg-binop cg 'eq)
     19   (cg-return cg)
     20   (cg-fn-end cg)
     21   (write-bv-fd 1 (cg-finish cg)))