1const std = @import("std");
  2const minInt = std.math.minInt;
  3const maxInt = std.math.maxInt;
  4const builtin = @import("builtin");
  5
  6test "int comparison elision" {
  7    if (builtin.zig_backend == .stage2_riscv64) return error.SkipZigTest;
  8
  9    testIntEdges(u0);
 10    testIntEdges(i0);
 11    testIntEdges(u1);
 12    testIntEdges(i1);
 13    testIntEdges(u4);
 14    testIntEdges(i4);
 15
 16    // TODO: support int types > 128 bits wide in other backends
 17    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
 18    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
 19    if (builtin.zig_backend == .stage2_spirv) return error.SkipZigTest;
 20
 21    // TODO: panic: integer overflow with int types > 65528 bits wide
 22    // TODO: LLVM generates too many parameters for wasmtime when splitting up int > 64000 bits wide
 23    testIntEdges(u64000);
 24    testIntEdges(i64000);
 25}
 26
 27// All comparisons in this test have a guaranteed result,
 28// so one branch of each 'if' should never be analyzed.
 29fn testIntEdges(comptime T: type) void {
 30    const min = minInt(T);
 31    const max = maxInt(T);
 32
 33    var runtime_val: T = undefined;
 34    _ = &runtime_val;
 35
 36    if (min > runtime_val) @compileError("analyzed impossible branch");
 37    if (min <= runtime_val) {} else @compileError("analyzed impossible branch");
 38    if (runtime_val < min) @compileError("analyzed impossible branch");
 39    if (runtime_val >= min) {} else @compileError("analyzed impossible branch");
 40
 41    if (min - 1 > runtime_val) @compileError("analyzed impossible branch");
 42    if (min - 1 >= runtime_val) @compileError("analyzed impossible branch");
 43    if (min - 1 < runtime_val) {} else @compileError("analyzed impossible branch");
 44    if (min - 1 <= runtime_val) {} else @compileError("analyzed impossible branch");
 45    if (min - 1 == runtime_val) @compileError("analyzed impossible branch");
 46    if (min - 1 != runtime_val) {} else @compileError("analyzed impossible branch");
 47    if (runtime_val < min - 1) @compileError("analyzed impossible branch");
 48    if (runtime_val <= min - 1) @compileError("analyzed impossible branch");
 49    if (runtime_val > min - 1) {} else @compileError("analyzed impossible branch");
 50    if (runtime_val >= min - 1) {} else @compileError("analyzed impossible branch");
 51    if (runtime_val == min - 1) @compileError("analyzed impossible branch");
 52    if (runtime_val != min - 1) {} else @compileError("analyzed impossible branch");
 53
 54    if (max >= runtime_val) {} else @compileError("analyzed impossible branch");
 55    if (max < runtime_val) @compileError("analyzed impossible branch");
 56    if (runtime_val <= max) {} else @compileError("analyzed impossible branch");
 57    if (runtime_val > max) @compileError("analyzed impossible branch");
 58
 59    if (max + 1 > runtime_val) {} else @compileError("analyzed impossible branch");
 60    if (max + 1 >= runtime_val) {} else @compileError("analyzed impossible branch");
 61    if (max + 1 < runtime_val) @compileError("analyzed impossible branch");
 62    if (max + 1 <= runtime_val) @compileError("analyzed impossible branch");
 63    if (max + 1 == runtime_val) @compileError("analyzed impossible branch");
 64    if (max + 1 != runtime_val) {} else @compileError("analyzed impossible branch");
 65    if (runtime_val < max + 1) {} else @compileError("analyzed impossible branch");
 66    if (runtime_val <= max + 1) {} else @compileError("analyzed impossible branch");
 67    if (runtime_val > max + 1) @compileError("analyzed impossible branch");
 68    if (runtime_val >= max + 1) @compileError("analyzed impossible branch");
 69    if (runtime_val == max + 1) @compileError("analyzed impossible branch");
 70    if (runtime_val != max + 1) {} else @compileError("analyzed impossible branch");
 71
 72    const undef_const: T = undefined;
 73
 74    if (min > undef_const) @compileError("analyzed impossible branch");
 75    if (min <= undef_const) {} else @compileError("analyzed impossible branch");
 76    if (undef_const < min) @compileError("analyzed impossible branch");
 77    if (undef_const >= min) {} else @compileError("analyzed impossible branch");
 78
 79    if (min - 1 > undef_const) @compileError("analyzed impossible branch");
 80    if (min - 1 >= undef_const) @compileError("analyzed impossible branch");
 81    if (min - 1 < undef_const) {} else @compileError("analyzed impossible branch");
 82    if (min - 1 <= undef_const) {} else @compileError("analyzed impossible branch");
 83    if (min - 1 == undef_const) @compileError("analyzed impossible branch");
 84    if (min - 1 != undef_const) {} else @compileError("analyzed impossible branch");
 85    if (undef_const < min - 1) @compileError("analyzed impossible branch");
 86    if (undef_const <= min - 1) @compileError("analyzed impossible branch");
 87    if (undef_const > min - 1) {} else @compileError("analyzed impossible branch");
 88    if (undef_const >= min - 1) {} else @compileError("analyzed impossible branch");
 89    if (undef_const == min - 1) @compileError("analyzed impossible branch");
 90    if (undef_const != min - 1) {} else @compileError("analyzed impossible branch");
 91
 92    if (max >= undef_const) {} else @compileError("analyzed impossible branch");
 93    if (max < undef_const) @compileError("analyzed impossible branch");
 94    if (undef_const <= max) {} else @compileError("analyzed impossible branch");
 95    if (undef_const > max) @compileError("analyzed impossible branch");
 96
 97    if (max + 1 > undef_const) {} else @compileError("analyzed impossible branch");
 98    if (max + 1 >= undef_const) {} else @compileError("analyzed impossible branch");
 99    if (max + 1 < undef_const) @compileError("analyzed impossible branch");
100    if (max + 1 <= undef_const) @compileError("analyzed impossible branch");
101    if (max + 1 == undef_const) @compileError("analyzed impossible branch");
102    if (max + 1 != undef_const) {} else @compileError("analyzed impossible branch");
103    if (undef_const < max + 1) {} else @compileError("analyzed impossible branch");
104    if (undef_const <= max + 1) {} else @compileError("analyzed impossible branch");
105    if (undef_const > max + 1) @compileError("analyzed impossible branch");
106    if (undef_const >= max + 1) @compileError("analyzed impossible branch");
107    if (undef_const == max + 1) @compileError("analyzed impossible branch");
108    if (undef_const != max + 1) {} else @compileError("analyzed impossible branch");
109}
110
111test "comparison elided on large integer value" {
112    try std.testing.expect(-1 == @as(i8, -3) >> 2);
113    try std.testing.expect(-1 == -3 >> 2000);
114}