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Hint-directed fast arithmetic: fl*/fx* from ^double/^long (round 1)

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A ^double/^long param hint (or a float literal) now drives Chez flonum/fixnum
ops instead of generic arithmetic — JVM-style primitive hints, available in every
build and at -e (not gated on direct-linking or whole-program inference).

New pass jolt.passes.numeric: a local forward type-flow seeded from ^double/^long
fn-param hints (analyzer attaches :nhints per arity) and float literals,
propagated through let inits / arithmetic / if / do. It tags an arithmetic invoke
:num-kind :double|:long when every operand is that kind (an integer literal is a
wildcard, coerced to a flonum in a double op). The back end lowers a tagged node
to fl+/fl-/fl*/fl//fl<?/... or fx+/fx*/fx1+/fxquotient/... (unchecked-add etc.
join the fixnum path; == too). Runs last in run-passes, both branches.

Soundness: :long is seeded ONLY from an explicit ^long hint, never a bare integer
literal, so un-hinted integer code keeps jolt's arbitrary-precision numbers — no
fixnum-overflow surprise, no corpus divergence. :double comes from ^double hints
and float literals (flonum arithmetic is always flonum, matching the generic
result). A ^long hint is a promise the value is a fixnum: fx+ raises on overflow,
like a JVM fixed-width long.

Numeric-hinted params coerce at fn entry (exact->inexact / jolt->fx), the way the
JVM coerces a primitive parameter — so the body's fl*/fx* ops can rely on the
type even when a caller passes an exact int (e.g. Chez's (* 0 1.0) => exact 0).

Round 1 specializes hinted straight-line / fn-body arithmetic. fl-ops are ~4x
generic in a tight Chez loop, but realizing that on loop-carried accumulators
needs loop-var typing — round 2. Sound foundation, gated by test/chez/numeric-test.ss.
This commit is contained in:
Yogthos 2026-06-23 16:43:55 -04:00
parent 2c18fcdc61
commit 59905a71fd
9 changed files with 567 additions and 236 deletions
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1
host/chez/emit-image.ss
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@ -96,6 +96,7 @@
(cons "jolt.analyzer" "jolt-core/jolt/analyzer.clj")
(cons "jolt.backend-scheme" "jolt-core/jolt/backend_scheme.clj")
(cons "jolt.passes.fold" "jolt-core/jolt/passes/fold.clj")
(cons "jolt.passes.numeric" "jolt-core/jolt/passes/numeric.clj")
(cons "jolt.passes.inline" "jolt-core/jolt/passes/inline.clj")
(cons "jolt.passes.types.lattice" "jolt-core/jolt/passes/types/lattice.clj")
(cons "jolt.passes.types" "jolt-core/jolt/passes/types.clj")