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https://github.com/vercel-labs/scriptc.git
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Search arrays of objects and strings inline
indexOf and includes on arrays of class instances, records, arrays, maps, sets, typed arrays and strings call an internal helper that LLVM inlines. When the array's hole-free prefix covers its whole length, the helper scans the dense slots itself: references compare as 64-bit slots, four per branch, and strings compare by pointer, then length, then bytes, with strings of up to 16 bytes compared as two words and longer ones through scr_str_eq. Arrays with holes or sparse entries, and every other element type, keep the runtime search.
This commit is contained in:
Chris Tate
@@ -0,0 +1,85 @@
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import { expect, test } from "vitest";
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import {
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F64,
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STRING,
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VOID,
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arrayOf,
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type IrExpr,
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type IrModule,
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type IrType,
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} from "../../ir/ir.js";
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import { emitLlvmModule } from "./emitter.js";
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const loc = { file: "array-search.ts", start: 0, end: 0 };
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const ref = (localId: string, type: IrType): IrExpr => ({ kind: "varRef", localId, type, loc });
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/** A module whose function `find` returns `a.method(v)` for an array `a`
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* of `elem`. */
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function module(elem: IrType, method: "indexOf" | "includes"): IrModule {
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const arr = arrayOf(elem);
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const search: IrExpr = {
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kind: "arrIntrinsic",
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method,
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receiver: ref("a", arr),
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args: [ref("v", elem)],
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type: method === "includes" ? { kind: "bool" } : F64,
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loc,
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};
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return {
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irVersion: 16,
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sourceFile: loc.file,
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entry: "__main",
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functions: [
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{ name: "__main", params: [], returnType: VOID, locals: [], body: [], loc },
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{
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name: "find",
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params: [
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{ name: "a", localId: "a", type: arr },
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{ name: "v", localId: "v", type: elem },
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],
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returnType: search.type,
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locals: [
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{ id: "a", name: "a", type: arr, mutable: false },
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{ id: "v", name: "v", type: elem, mutable: false },
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],
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body: [{ kind: "return", value: search, loc }],
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loc,
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},
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],
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};
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}
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function helper(llvm: string, name: string): string {
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return new RegExp(`^define internal double @${name}\\([^]*?^}`, "m").exec(llvm)![0];
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}
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test.each([32, 64] as const)("string arrays search inline (%i-bit)", (bits) => {
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const sz = bits === 64 ? "i64" : "i32";
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const llvm = emitLlvmModule(module(STRING, "indexOf"), { pointerBits: bits });
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expect(llvm).toMatch(/call double @sc_arr_index_of_str\(ptr .*, ptr .*\)/);
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const fn = helper(llvm, "sc_arr_index_of_str");
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// Dense arrays only (filled == len); everything else is the runtime search.
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expect(fn).toMatch(new RegExp(`icmp eq ${sz} %f, %len`));
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expect(fn).toContain("call double @scr_arr_index_of_ref(ptr %a, ptr %v)");
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// Pointer identity, the length, then up to 16 bytes as words; longer
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// strings compare in the runtime.
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expect(fn).toContain("icmp eq ptr %s, %v");
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expect(fn).toMatch(/load i64, ptr %sap, align 1/);
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expect(fn).toContain("call zeroext i1 @scr_str_eq(ptr %s, ptr %v)");
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});
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test.each([32, 64] as const)("reference arrays compare slots, four per step (%i-bit)", (bits) => {
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const llvm = emitLlvmModule(module(arrayOf(F64), "includes"), { pointerBits: bits });
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expect(llvm).toMatch(/call double @sc_arr_index_of_ptr\(ptr .*, ptr .*\)/);
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expect(llvm).toMatch(/fcmp oge double %.*, 0\.0/);
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const fn = helper(llvm, "sc_arr_index_of_ptr");
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expect(fn.match(/icmp eq i64 %qs\d, %needle/g)).toHaveLength(4);
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expect(fn).toContain("icmp eq i64 %s, %needle");
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expect(llvm).not.toContain("sc_arr_index_of_str");
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});
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test("number arrays keep the runtime search", () => {
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const llvm = emitLlvmModule(module(F64, "indexOf"), { pointerBits: 64 });
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expect(llvm).toContain("call double @scr_arr_index_of_f64(");
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expect(llvm).not.toContain("sc_arr_index_of_");
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});
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@@ -0,0 +1,194 @@
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/* Inline indexOf / includes over arrays of references.
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*
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* The runtime search (scr_arr_index_of_ref) checks each slot's state byte and
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* dispatches on the element kind for every element. When the array's
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* hole-free prefix covers its whole length (filled == len, so there are no
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* holes and no sparse entries), the internal helpers below scan the dense
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* slots directly, and LLVM inlines them at the call site:
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*
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* - sc_arr_index_of_ptr, for element types whose strict equality and
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* SameValueZero are both pointer identity (class instances, records,
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* arrays, maps, sets, typed arrays): 64-bit compares, four slots per
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* branch.
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* - sc_arr_index_of_str, for strings: pointer identity, then the length,
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* then the bytes. Strings of up to 16 bytes compare as two words; a short
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* string's word is the eight bytes ending at its last byte, which start
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* in the string header when it is shorter than eight bytes and so stay
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* inside the object, shifted down past the header bytes. Longer strings
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* compare with scr_str_eq.
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*
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* Any other array takes the runtime search. Both helpers answer the index,
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* or -1; includes compares the answer with 0, since for these element types
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* SameValueZero and strict equality agree. Every target scriptc builds for
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* is little-endian, which the short-string words assume.
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*/
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import type { IrType } from "../../ir/ir.js";
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import { FN_ATTRS } from "./shapes.js";
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export type ArraySearchKind = "ptr" | "str";
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/** The inline search for arrays of `elem`, or null for the runtime search. */
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export function arraySearchKind(elem: IrType): ArraySearchKind | null {
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switch (elem.kind) {
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case "object":
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case "record":
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case "array":
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case "map":
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case "set":
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case "bytes":
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return "ptr";
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case "string":
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return "str";
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default:
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return null;
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}
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}
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export function arraySearchHelperName(kind: ArraySearchKind): string {
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return kind === "ptr" ? "sc_arr_index_of_ptr" : "sc_arr_index_of_str";
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}
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/** The definitions of the helpers in `kinds`; they declare their slow paths
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* through `declare`. */
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export function emitArraySearchHelpers(
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kinds: ReadonlySet<ArraySearchKind>,
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sz: string,
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declare: (line: string) => void,
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): string[] {
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const defs: string[] = [];
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for (const kind of [...kinds].sort()) {
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declare("declare double @scr_arr_index_of_ref(ptr, ptr)");
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const widen = sz === "i64" ? " %f = zext i32 %f32 to i64" : " %f = add i32 %f32, 0";
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defs.push(
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`define internal double @${arraySearchHelperName(kind)}(ptr %a, ptr %v) ${FN_ATTRS} {`,
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`entry:`,
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` %lenp = getelementptr inbounds %ScrArr, ptr %a, i32 0, i32 1`,
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` %len = load ${sz}, ptr %lenp`,
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` %fp = getelementptr inbounds %ScrArr, ptr %a, i32 0, i32 6`,
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` %f32 = load i32, ptr %fp`,
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widen,
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` %dense = icmp eq ${sz} %f, %len`,
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` br i1 %dense, label %scan, label %slow`,
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`scan:`,
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` %dp = getelementptr inbounds %ScrArr, ptr %a, i32 0, i32 8`,
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` %data = load ptr, ptr %dp`,
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);
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if (kind === "ptr") {
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defs.push(
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` %needle = ptrtoint ptr %v to i64`,
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// Four slots per step with one branch, then one at a time.
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` br label %quad`,
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`quad:`,
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` %q = phi ${sz} [ 0, %scan ], [ %qnext, %quadmiss ]`,
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` %qend = add ${sz} %q, 4`,
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` %qfits = icmp ule ${sz} %qend, %len`,
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` br i1 %qfits, label %quadbody, label %loop`,
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`quadbody:`,
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...[0, 1, 2, 3].flatMap((k) => [
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` %qi${k} = add ${sz} %q, ${k}`,
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` %qp${k} = getelementptr inbounds i64, ptr %data, ${sz} %qi${k}`,
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` %qs${k} = load i64, ptr %qp${k}`,
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` %qh${k} = icmp eq i64 %qs${k}, %needle`,
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]),
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` %qh01 = or i1 %qh0, %qh1`,
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` %qh23 = or i1 %qh2, %qh3`,
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` %qhit = or i1 %qh01, %qh23`,
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` br i1 %qhit, label %loop, label %quadmiss`,
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`quadmiss:`,
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` %qnext = add ${sz} %q, 4`,
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` br label %quad`,
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// The single-slot loop finishes the tail, or finds the hit inside a
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// step that had one.
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`loop:`,
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` %i = phi ${sz} [ %q, %quad ], [ %q, %quadbody ], [ %next, %cont ]`,
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` %done = icmp eq ${sz} %i, %len`,
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` br i1 %done, label %miss, label %body`,
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`body:`,
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` %sp = getelementptr inbounds i64, ptr %data, ${sz} %i`,
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` %s = load i64, ptr %sp`,
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` %hit = icmp eq i64 %s, %needle`,
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` br i1 %hit, label %found, label %cont`,
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);
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} else {
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declare("declare zeroext i1 @scr_str_eq(ptr, ptr)");
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defs.push(
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` %vlp = getelementptr inbounds %ScrStr, ptr %v, i32 0, i32 1`,
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` %vlen = load ${sz}, ptr %vlp`,
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` %vdata = getelementptr inbounds %ScrStr, ptr %v, i32 1`,
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` br label %loop`,
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`loop:`,
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` %i = phi ${sz} [ 0, %scan ], [ %next, %cont ]`,
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` %done = icmp eq ${sz} %i, %len`,
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` br i1 %done, label %miss, label %body`,
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`body:`,
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` %sp = getelementptr inbounds i64, ptr %data, ${sz} %i`,
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` %sw = load i64, ptr %sp`,
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` %s = inttoptr i64 %sw to ptr`,
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` %same = icmp eq ptr %s, %v`,
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` br i1 %same, label %found, label %length`,
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`length:`,
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` %slp = getelementptr inbounds %ScrStr, ptr %s, i32 0, i32 1`,
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` %slen = load ${sz}, ptr %slp`,
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` %samelen = icmp eq ${sz} %slen, %vlen`,
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` br i1 %samelen, label %bytes, label %cont`,
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// Same length: dispatch on it.
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`bytes:`,
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` %empty = icmp eq ${sz} %vlen, 0`,
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` br i1 %empty, label %found, label %nonempty`,
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`nonempty:`,
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` %short = icmp ult ${sz} %vlen, 8`,
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` br i1 %short, label %tiny, label %wide`,
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`tiny:`,
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` %sdata = getelementptr inbounds %ScrStr, ptr %s, i32 1`,
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` %back = sub ${sz} %vlen, 8`,
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` %sap = getelementptr inbounds i8, ptr %sdata, ${sz} %back`,
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` %vap = getelementptr inbounds i8, ptr %vdata, ${sz} %back`,
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` %sa = load i64, ptr %sap, align 1`,
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` %va = load i64, ptr %vap, align 1`,
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` %diff = xor i64 %sa, %va`,
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sz === "i64" ? ` %vlen64 = add i64 %vlen, 0` : ` %vlen64 = zext i32 %vlen to i64`,
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` %bits = shl i64 %vlen64, 3`,
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` %drop = sub i64 64, %bits`,
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` %kept = lshr i64 %diff, %drop`,
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` %tinyeq = icmp eq i64 %kept, 0`,
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` br i1 %tinyeq, label %found, label %cont`,
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`wide:`,
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` %fits = icmp ule ${sz} %vlen, 16`,
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` br i1 %fits, label %two, label %long`,
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`two:`,
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` %sdata2 = getelementptr inbounds %ScrStr, ptr %s, i32 1`,
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` %s0 = load i64, ptr %sdata2, align 1`,
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` %v0 = load i64, ptr %vdata, align 1`,
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` %tail = sub ${sz} %vlen, 8`,
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` %s1p = getelementptr inbounds i8, ptr %sdata2, ${sz} %tail`,
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` %v1p = getelementptr inbounds i8, ptr %vdata, ${sz} %tail`,
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` %s1 = load i64, ptr %s1p, align 1`,
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` %v1 = load i64, ptr %v1p, align 1`,
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` %d0 = xor i64 %s0, %v0`,
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` %d1 = xor i64 %s1, %v1`,
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` %d = or i64 %d0, %d1`,
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` %twoeq = icmp eq i64 %d, 0`,
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` br i1 %twoeq, label %found, label %cont`,
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`long:`,
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` %longeq = call zeroext i1 @scr_str_eq(ptr %s, ptr %v)`,
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` br i1 %longeq, label %found, label %cont`,
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);
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}
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defs.push(
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`cont:`,
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` %next = add ${sz} %i, 1`,
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` br label %loop`,
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`found:`,
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` %at = uitofp ${sz} %i to double`,
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` ret double %at`,
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`miss:`,
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` ret double -1.0`,
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`slow:`,
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` %r = call double @scr_arr_index_of_ref(ptr %a, ptr %v)`,
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` ret double %r`,
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`}`,
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``,
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);
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}
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return defs;
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}
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@@ -1,3 +1,4 @@
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import { type ArraySearchKind, emitArraySearchHelpers } from "./array-search.js";
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import { emitLlvmLayouts } from "./layouts.js";
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import { compileRegexMatcher, type RegexMatcherCode } from "./regex-matchers.js";
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import { CYC_BUF, CYC_HDR, FIRST_EMITTED_CYC_KIND, inlineAllocSupported } from "./alloc.js";
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@@ -770,6 +771,8 @@ export class LlEmitter {
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* typeKey → thunk symbol. */
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readonly resolveThunks = new Map<string, string>();
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readonly resolveThunkDefs: string[] = [];
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/** Inline array searches used by the module (array-search.ts). */
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readonly arraySearchKinds = new Set<ArraySearchKind>();
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/** Typed-ref recipe constants by type key (lazy receivers). */
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readonly typedRefRecipes = new Map<string, string>();
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/** ReadableStream.from adapters keep typed arrays by reference and box
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@@ -1977,6 +1980,7 @@ export class LlEmitter {
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// write/abort declarations).
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const helpers = [
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...this.helperDefs(),
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...emitArraySearchHelpers(this.arraySearchKinds, this.sizeType, (line) => this.declare(line)),
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...emitClassMembershipHelper(this.classMeta, this.sizeType),
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...(this.publishWalkersCache?.defs() ?? []),
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...this.publishedClassNamesDefs(),
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@@ -1,4 +1,5 @@
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/* Focused LLVM expression emission extracted from emitter.ts. */
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import { arraySearchHelperName, arraySearchKind } from "./array-search.js";
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import { InternalCompilerError } from "../../errors.js";
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import { isStableReceiverOperand, undefinedArmTag } from "../../ir/analysis.js";
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import { type IrExpr, type IrType, isRefCounted, typeEquals, typeKey } from "../../ir/ir.js";
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@@ -719,16 +720,38 @@ export function emitArrIntrinsic(
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case "indexOf": {
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// The needle is BORROWED (released with this statement's frame);
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// the ref variant dispatches on the array's element kind (strings
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// by content, everything else by pointer). Strict equality.
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// by content, everything else by pointer). Strict equality. Arrays of
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// objects and strings scan inline (array-search.ts).
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const v = host.emitExpr(e.args[0]!);
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const search = acc === "ref" ? arraySearchKind(elem) : null;
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if (search !== null) {
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host.arraySearchKinds.add(search);
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const t = B.tmp();
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B.line(
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`${t} = call double @${arraySearchHelperName(search)}(ptr ${r.name}, ptr ${v.name})`,
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);
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return { name: t, type: e.type };
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}
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host.declare(`declare double @scr_arr_index_of_${acc}(ptr, ${accArg})`);
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const t = B.tmp();
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B.line(`${t} = call double @scr_arr_index_of_${acc}(ptr ${r.name}, ${accTy} ${v.name})`);
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return { name: t, type: e.type };
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}
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case "includes": {
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// Borrowed needle, SameValueZero (NaN matches NaN).
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// Borrowed needle, SameValueZero (NaN matches NaN). For the inline
|
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// searches SameValueZero is strict equality.
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const v = host.emitExpr(e.args[0]!);
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const search = acc === "ref" ? arraySearchKind(elem) : null;
|
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if (search !== null) {
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host.arraySearchKinds.add(search);
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const at = B.tmp(),
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t = B.tmp();
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B.line(
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`${at} = call double @${arraySearchHelperName(search)}(ptr ${r.name}, ptr ${v.name})`,
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);
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B.line(`${t} = fcmp oge double ${at}, 0.0`);
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return { name: t, type: e.type };
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}
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host.declare(`declare zeroext i1 @scr_arr_includes_${acc}(ptr, ${accArg})`);
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const t = B.tmp();
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B.line(`${t} = call zeroext i1 @scr_arr_includes_${acc}(ptr ${r.name}, ${accTy} ${v.name})`);
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+6
@@ -0,0 +1,6 @@
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||||
{
|
||||
"order": [
|
||||
"<repo>/tests/corpus/5551-array-search-references.ts"
|
||||
],
|
||||
"diags": []
|
||||
}
|
||||
@@ -0,0 +1,80 @@
|
||||
// indexOf and includes on arrays of objects, records, arrays, maps, sets,
|
||||
// typed arrays and strings: dense arrays, arrays with holes and sparse
|
||||
// entries (the runtime search), duplicates (the first index), and strings of
|
||||
// every length class built separately, differing at each position.
|
||||
class Item {
|
||||
id: number;
|
||||
constructor(id: number) {
|
||||
this.id = id;
|
||||
}
|
||||
}
|
||||
const items: Item[] = [];
|
||||
for (let i = 0; i < 37; i++) items.push(new Item(i));
|
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const stranger = new Item(99);
|
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const objectResults: number[] = [];
|
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for (let i = 0; i < 37; i++) objectResults.push(items.indexOf(items[i]!));
|
||||
objectResults.push(items.indexOf(stranger), items.includes(stranger) ? 1 : 0, items.includes(items[36]!) ? 1 : 0);
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items.push(items[5]!);
|
||||
objectResults.push(items.indexOf(items[5]!), items.lastIndexOf(items[5]!));
|
||||
console.log(objectResults.join(","));
|
||||
|
||||
// Holes and sparse entries.
|
||||
const holey: Item[] = items.slice(0, 10);
|
||||
holey.length = 20;
|
||||
holey[15] = stranger;
|
||||
console.log(holey.indexOf(stranger), holey.includes(stranger), holey.indexOf(items[3]!), holey.indexOf(items[12]!));
|
||||
const sparse: Item[] = [items[0]!, items[1]!];
|
||||
sparse[5000] = stranger;
|
||||
console.log(sparse.indexOf(stranger), sparse.includes(items[1]!), sparse.indexOf(items[2]!));
|
||||
const emptied: Item[] = [items[0]!];
|
||||
emptied.pop();
|
||||
console.log(emptied.indexOf(items[0]!), emptied.includes(items[0]!), emptied.length);
|
||||
|
||||
// Mutation between searches.
|
||||
const moving = items.slice(0, 8);
|
||||
moving.shift();
|
||||
moving.splice(2, 1);
|
||||
moving.unshift(stranger);
|
||||
console.log(moving.indexOf(stranger), moving.indexOf(items[0]!), moving.indexOf(items[3]!), moving.indexOf(items[7]!));
|
||||
|
||||
// Other reference element kinds.
|
||||
type Point = { x: number; y: number };
|
||||
const points: Point[] = [{ x: 1, y: 2 }, { x: 1, y: 2 }];
|
||||
const p0 = points[0]!;
|
||||
console.log(points.indexOf(p0), points.indexOf(points[1]!), points.indexOf({ x: 1, y: 2 }), points.includes(p0));
|
||||
const rows: number[][] = [[1], [2], [1]];
|
||||
console.log(rows.indexOf(rows[2]!), rows.includes([1]), rows.indexOf(rows[1]!));
|
||||
const maps: Map<string, number>[] = [new Map(), new Map()];
|
||||
const sets: Set<number>[] = [new Set([1]), new Set([1])];
|
||||
const buffers: Uint8Array[] = [new Uint8Array(2), new Uint8Array(2)];
|
||||
console.log(maps.indexOf(maps[1]!), sets.indexOf(sets[1]!), sets.includes(new Set([1])), buffers.indexOf(buffers[1]!));
|
||||
|
||||
// Strings: lengths 0 to 40, each built at run time, differing at each position.
|
||||
function build(n: number, at: number, ch: string): string {
|
||||
let s = "";
|
||||
for (let i = 0; i < n; i++) s += i === at ? ch : String.fromCharCode(97 + (i % 26));
|
||||
return s;
|
||||
}
|
||||
let out = "";
|
||||
for (let n = 0; n <= 40; n++) {
|
||||
const words: string[] = [];
|
||||
for (let at = 0; at < n; at++) words.push(build(n, at, "Z"));
|
||||
words.push(build(n, -1, ""));
|
||||
for (let at = 0; at < n; at++) {
|
||||
const probe = build(n, at, "Z");
|
||||
out += words.indexOf(probe) === at ? "." : "x";
|
||||
}
|
||||
out += words.indexOf(build(n, -1, "")) === n ? "." : "x";
|
||||
out += words.includes(build(n + 1, -1, "")) ? "x" : ".";
|
||||
out += words.indexOf(build(n, n - 1, "Y")) === -1 || n === 0 ? "." : "x";
|
||||
out += "|";
|
||||
}
|
||||
console.log(out);
|
||||
const names = ["", "a", "é", "日本", "naïve", "naive", "😀", "abcdefgh", "abcdefghi", "abcdefghabcdefgh", "abcdefghabcdefghX"];
|
||||
const lookups = names.map((name) => (name + "!").slice(0, name.length));
|
||||
console.log(lookups.map((name) => names.indexOf(name)).join(","), names.includes("na" + "ïve"), names.indexOf("日"), names.indexOf("abcdefghabcdefgY"));
|
||||
const dup = ["k", "k", "q", "k"];
|
||||
console.log(dup.indexOf("k"), dup.indexOf("q"), dup.includes("z"), dup.lastIndexOf("k"));
|
||||
const holeyNames: string[] = ["a", "b"];
|
||||
holeyNames[4] = "e";
|
||||
console.log(holeyNames.indexOf("e"), holeyNames.includes("b"), holeyNames.indexOf("c"));
|
||||
Reference in New Issue
Block a user