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#import "Basic";
#import "Compiler";
#import "Math";
#run test_math_ext();
test_math_ext :: () {
set_build_options_dc(.{do_output=false});
write_strings("=====================\n", "--- Test Math_Ext ---\n");
Test_Inputs :: struct(ia: $T, ib: T, ir: T, is: bool) {
// t: Type;
a := ia;
b := ib;
r := ir;
s := is;
};
/*
tests := Test_Inputs.[
// .{1, 2, 3, false},
];
for * tests {
result, saturated := add(cast(it.t)it.a, cast(it.t)it.b);
assert(result == it.r && saturated == it.s, "Failed: % %\n", result, saturated);
}
*/
t1a := S64_MAX;
t1b := 0;
t1v, t1r := add(t1a, t1b);
assert(t1v == S64_MAX && t1r == false, "Failed: % %\n", t1v, t1r);
write_string("t1: OK\n");
// t2a := S64_MAX;
// t2b := 1;
// t2v, t2r := add(t2a, t2b);
// assert(t2v == S64_MAX && t2r == true, "Failed: % %\n", t2v, t2r);
}
add_int64 :: (x :s64, y: s64) -> s64 #dump { // TODO Comparing implementations.
return
ifx (y > 0 && x > S64_MAX - y) then S64_MAX else
ifx (y < 0 && x < S64_MIN - y) then S64_MIN else
x + y;
}
sub_int64 :: (x :s64, y :s64) -> s64 {
return
ifx (y < 0 && x > S64_MAX + y) then S64_MAX else
ifx (y > 0 && x < S64_MIN + y) then S64_MIN else
x - y;
}
add :: (x: s64, y: s64) -> result: s64, saturated: bool #dump { // TODO Comparing implementaitons using dump
#if CPU == .X64 {
saturated := false;
...test this case...
if (y > 0 && x > S64_MAX - y) then return S64_MAX, true;
if (y < 0 && x < S64_MIN - y) then return S64_MIN, true;
return x + y, false;
// if (y > 0 && x > S64_MAX - y) then return S64_MAX, true;
// if (y < 0 && x < S64_MIN - y) then return S64_MIN, true;
// return x + y, false;
} else {
result: s64 = ---;
flag: bool = ---;
#asm {
mov d: gpr === d, 9223372036854775807;
mov a: gpr === a, x;
mov b: gpr === b, y;
add a, b;
seto flag; // Flag overflow.
mov result, a;
mov a, x;
shr a, 63;
add a, d;
mov c: gpr, x;
xor c, b;
xor b, result;
not b;
or c, b;
test c, c;
cmovns result, a;
}
return result, flag;
}
}
/*
// value_a: s64 = 2;
// value_b: s64 = S64_MAX-1;
value_a: s64 = -2;
value_b: s64 = S64_MIN+1;
print(">%\n", S64_MAX);
argx := get_command_line_arguments();
if argx.count > 1
value_a = parse_int(*argx[1]);
if argx.count > 2
value_b = parse_int(*argx[2]);
result: s64 = ---;
flags: s64;// = ---;
#asm LAHF_SAHF { // TODO Remove LAHF_SAHF it not required.
// Code from https://locklessinc.com/articles/sat_arithmetic/
// value_a === b;
// value_b === c;
// add value_a, value_b;
// mov result, value_a;
// Version 1
// mov b: gpr === b, value_a;
// mov c: gpr === c, value_b;
// add b, c;
// mov result, b;
// seto flags;
// cmovns b, c;
// s64b sat_adds64b(s64b x, s64b y)
// {
// u64b ux = x;
// u64b uy = y;
// u64b res = ux + uy;
//
// ux = (ux >> 63) + LONG_MAX;
//
// /* Force compiler to use cmovns instruction */
// if ((s64b) ((ux ^ uy) | ~(uy ^ res)) >= 0)
// {
// res = ux;
// }
//
// return res;
// }
// Version 2 - WORKS
mov d: gpr === d, 9223372036854775807;
mov a: gpr === a, value_a;
mov b: gpr === b, value_b;
add a, b;
seto flags; // Flag overflow.
mov result, a;
mov a, value_a;
shr a, 63;
add a, d;
mov c: gpr, value_a;
xor c, b;
xor b, result;
not b;
or c, b;
test c, c;
cmovns result, a;
// s64b sat_subs64b(s64b x, s64b y)
// {
// u64b ux = x;
// u64b uy = y;
// u64b res = ux - uy;
//
// ux = (ux >> 63) + LONG_MAX;
//
// // Force compiler to use cmovns instruction
// if ((s64b)((ux ^ uy) & (ux ^ res)) < 0)
// {
// res = ux;
// }
//
// return res;
// }
// TODO Use https://godbolt.org/ to help
}
print("% + % = %\n", value_a, value_b, result);
print("flag: %\n", flags);
return;
*/
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