43 lines
1.0 KiB
Zig
43 lines
1.0 KiB
Zig
const builtin = @import("builtin");
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const compiler_rt = @import("../compiler_rt.zig");
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pub extern fn __ashrti3(a: i128, b: i32) i128 {
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var input = twords{ .all = a };
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var result: twords = undefined;
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if (b > 63) {
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// 64 <= b < 128
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result.s.low = input.s.high >> @intCast(u6, b - 64);
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result.s.high = input.s.high >> 63;
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} else {
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// 0 <= b < 64
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if (b == 0) return a;
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result.s.low = input.s.high << @intCast(u6, 64 - b);
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// Avoid sign-extension here
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result.s.low |= @bitCast(i64, @bitCast(u64, input.s.low) >> @intCast(u6, b));
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result.s.high = input.s.high >> @intCast(u6, b);
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}
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return result.all;
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}
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const twords = extern union {
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all: i128,
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s: S,
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const S = if (builtin.endian == builtin.Endian.Little)
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struct {
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low: i64,
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high: i64,
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}
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else
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struct {
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high: i64,
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low: i64,
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};
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};
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test "import ashrti3" {
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_ = @import("ashrti3_test.zig");
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}
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