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Diffstat (limited to 'linux/409print-float-hex.mu')
| -rw-r--r-- | linux/409print-float-hex.mu | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/linux/409print-float-hex.mu b/linux/409print-float-hex.mu new file mode 100644 index 00000000..043576b6 --- /dev/null +++ b/linux/409print-float-hex.mu @@ -0,0 +1,196 @@ +# quick-n-dirty way to print out floats in hex +# https://www.exploringbinary.com/hexadecimal-floating-point-constants + +# example: +# 0.5 = 0x3f000000 = 0011| 1111 | 0000 | 0000 | 0000 | 0000 | 0000 | 0000 +# = 0 | 01111110 | 00000000000000000000000 +# + exponent mantissa +# = 0 | 00000000000000000000000 | 01111110 +# mantissa exponent +# = 0 | 000000000000000000000000 | 01111110 +# zero-pad mantissa exponent +# = +1.000000 P -01 +fn test-print-float-hex-normal { + var screen-on-stack: screen + var screen/esi: (addr screen) <- address screen-on-stack + initialize-screen screen, 5, 0x20 # 32 columns should be more than enough + # 0.5 + var half/xmm0: float <- rational 1, 2 + print-float-hex screen, half + check-screen-row screen, 1, "1.000000P-01 ", "F - test-print-float-hex-normal 0.5" + # 0.25 + clear-screen screen + var quarter/xmm0: float <- rational 1, 4 + print-float-hex screen, quarter + check-screen-row screen, 1, "1.000000P-02 ", "F - test-print-float-hex-normal 0.25" + # 0.75 + clear-screen screen + var three-quarters/xmm0: float <- rational 3, 4 + print-float-hex screen, three-quarters + check-screen-row screen, 1, "1.800000P-01 ", "F - test-print-float-hex-normal 0.75" + # 0.1 + clear-screen screen + var tenth/xmm0: float <- rational 1, 0xa + print-float-hex screen, tenth + check-screen-row screen, 1, "1.99999aP-04 ", "F - test-print-float-hex-normal 0.1" +} + +fn test-print-float-hex-integer { + var screen-on-stack: screen + var screen/esi: (addr screen) <- address screen-on-stack + initialize-screen screen, 5, 0x20 # 32 columns should be more than enough + # 1 + var one-f/xmm0: float <- rational 1, 1 + print-float-hex screen, one-f + check-screen-row screen, 1, "1.000000P00 ", "F - test-print-float-hex-integer 1" + # 2 + clear-screen screen + var two-f/xmm0: float <- rational 2, 1 + print-float-hex screen, two-f + check-screen-row screen, 1, "1.000000P01 ", "F - test-print-float-hex-integer 2" + # 10 + clear-screen screen + var ten-f/xmm0: float <- rational 0xa, 1 + print-float-hex screen, ten-f + check-screen-row screen, 1, "1.400000P03 ", "F - test-print-float-hex-integer 10" + # -10 + clear-screen screen + var minus-ten-f/xmm0: float <- rational -0xa, 1 + print-float-hex screen, minus-ten-f + check-screen-row screen, 1, "-1.400000P03 ", "F - test-print-float-hex-integer -10" +} + +fn test-print-float-hex-zero { + var screen-on-stack: screen + var screen/esi: (addr screen) <- address screen-on-stack + initialize-screen screen, 5, 0x20 # 32 columns should be more than enough + var zero: float + print-float-hex screen, zero + check-screen-row screen, 1, "0 ", "F - test-print-float-hex-zero" +} + +fn test-print-float-hex-negative-zero { + var screen-on-stack: screen + var screen/esi: (addr screen) <- address screen-on-stack + initialize-screen screen, 5, 0x20 # 32 columns should be more than enough + var n: int + copy-to n, 0x80000000 + var negative-zero/xmm0: float <- reinterpret n + print-float-hex screen, negative-zero + check-screen-row screen, 1, "-0 ", "F - test-print-float-hex-negative-zero" +} + +fn test-print-float-hex-infinity { + var screen-on-stack: screen + var screen/esi: (addr screen) <- address screen-on-stack + initialize-screen screen, 5, 0x20 # 32 columns should be more than enough + var n: int + # 0|11111111|00000000000000000000000 + # 0111|1111|1000|0000|0000|0000|0000|0000 + copy-to n, 0x7f800000 + var infinity/xmm0: float <- reinterpret n + print-float-hex screen, infinity + check-screen-row screen, 1, "Inf ", "F - test-print-float-hex-infinity" +} + +fn test-print-float-hex-negative-infinity { + var screen-on-stack: screen + var screen/esi: (addr screen) <- address screen-on-stack + initialize-screen screen, 5, 0x20 # 32 columns should be more than enough + var n: int + copy-to n, 0xff800000 + var negative-infinity/xmm0: float <- reinterpret n + print-float-hex screen, negative-infinity + check-screen-row screen, 1, "-Inf ", "F - test-print-float-hex-negative-infinity" +} + +fn test-print-float-hex-not-a-number { + var screen-on-stack: screen + var screen/esi: (addr screen) <- address screen-on-stack + initialize-screen screen, 5, 0x20 # 32 columns should be more than enough + var n: int + copy-to n, 0xffffffff # exponent must be all 1's, and mantissa must be non-zero + var negative-infinity/xmm0: float <- reinterpret n + print-float-hex screen, negative-infinity + check-screen-row screen, 1, "NaN ", "F - test-print-float-hex-not-a-number" +} + +fn print-float-hex screen: (addr screen), n: float { + # - special names + var bits/eax: int <- reinterpret n + compare bits, 0 + { + break-if-!= + print-string screen, "0" + return + } + compare bits, 0x80000000 + { + break-if-!= + print-string screen, "-0" + return + } + compare bits, 0x7f800000 + { + break-if-!= + print-string screen, "Inf" + return + } + compare bits, 0xff800000 + { + break-if-!= + print-string screen, "-Inf" + return + } + var exponent/ecx: int <- copy bits + exponent <- shift-right 0x17 # 23 bits of mantissa + exponent <- and 0xff + exponent <- subtract 0x7f + compare exponent, 0x80 + { + break-if-!= + print-string screen, "NaN" + return + } + # - regular numbers + var sign/edx: int <- copy bits + sign <- shift-right 0x1f + { + compare sign, 1 + break-if-!= + print-string screen, "-" + } + $print-float-hex:leading-digit: { + # check for subnormal numbers + compare exponent, -0x7f + { + break-if-!= + print-string screen, "0." + exponent <- increment + break $print-float-hex:leading-digit + } + # normal numbers + print-string screen, "1." + } + var mantissa/ebx: int <- copy bits + mantissa <- and 0x7fffff + mantissa <- shift-left 1 # pad to whole nibbles + print-int32-hex-bits screen, mantissa, 0x18 + # print exponent + print-string screen, "P" + compare exponent, 0 + { + break-if->= + print-string screen, "-" + } + var exp-magnitude/eax: int <- abs exponent + print-int32-hex-bits screen, exp-magnitude, 8 +} + +#? fn main -> _/ebx: int { +#? run-tests +#? #? test-print-float-hex-negative-zero +#? #? print-int32-hex 0, 0 +#? #? test-print-float-hex-normal +#? return 0 +#? } |