t27c on e8m0.t27 -- the MX shared scale byte, native

t27c 0.4.0 and zig 0.16.0 on the t27c lab (Railway): the E8M0 scale byte of OCP MX, 18 tests and 9 comptime invariants pass, and the Verilog backend's NaN check.

t27 $ sed -n 51,56p specs/numeric/e8m0.t27                                                              
    const E8M0_BITS       : u32 = 8;                                                                    
    const E8M0_BIAS       : i32 = 127;   // code 127 == 2^0                                             
    const E8M0_NAN_CODE   : u32 = 255;   // the one reserved code                                       
    const E8M0_MAX_FINITE : u32 = 254;   // largest finite code, 2^127                                  
    const E8M0_MIN_FINITE : u32 = 0;     // smallest finite code, 2^-127                                
    const E8M0_ONE        : u32 = 127;   // the code whose value is 1.0                                 
t27 $ t27c test-report specs/numeric/e8m0.t27 --specs-dir specs | sed -n '1,7p;$p'                      
--- test report: specs/numeric/e8m0.t27 ---                                                             

  tests       18                                                                                        
  pass        18                                                                                        
  FAIL        0                                                                                         
  invariants  9   proved -- comptime, so compiling IS the check                                         
  rate    100.0%                                                                                        
  vacuous passes  0 of 18  (passed with 0 runtime asserts executed)                                     
t27 $ t27c gen specs/numeric/e8m0.t27 > e8m0.zig && zig test e8m0.zig                                   
All 18 tests passed.                                                                                    
t27 $ t27c gen-verilog specs/numeric/e8m0.t27 | sed -n 69,78p                                           
    // function: e8m0_is_nan                                                                            
    function e8m0_is_nan; // -> bool                                                                    
        input [31:0] x;                                                                                 
        begin : e8m0_is_nan_body                                                                        
            reg __t27_ret;                                                                              
            __t27_ret = 1'b0;                                                                           
            e8m0_is_nan = (x == E8M0_NAN_CODE);                                                         
            __t27_ret = 1'b1;                                                                           
        end                                                                                             
    endfunction                                                                                         
t27 $

recorded 2026-10-06 14:11 UTCreal 19.9 sshown 19.9 sexit codes 0 0 0 0 0

$ git log -1 --format='%h %ad %s' --date=short -- specs/numeric/e8m0.t27 | cut -c1-100 $ sed -n 51,56p specs/numeric/e8m0.t27 $ t27c test-report specs/numeric/e8m0.t27 --specs-dir specs | sed -n '1,7p;$p' $ t27c gen specs/numeric/e8m0.t27 > e8m0.zig && zig test e8m0.zig $ t27c gen-verilog specs/numeric/e8m0.t27 | sed -n 69,78p

Staged: the prompt and the typing. Real: every byte the commands printed, at the time they printed it. Any silence longer than 2 s is shown for 2 s, and the title bar says so while it happens. Edited: home directory shown as ~.

GIF Preview card