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Int fallback restoration: Expand on the perf argument

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Tobias Bucher 2014-11-07 23:56:14 +01:00
parent 37f05a450d
commit 960661bea5
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@ -5,8 +5,8 @@
# Summary
Restore the integer inference fallback that was removed. Integer
literals whose type is unconstrained will default to `i32`, unlike the previous
fallback to `int`.
literals whose type is unconstrained will default to `i32`, unlike the
previous fallback to `int`.
Floating point literals will default to `f64`.
# Motivation
@ -125,6 +125,12 @@ the major calling conventions), it's faster than 64-bit integers in
arithmetic today, and is superior in memory usage while still providing
a reasonable range of possible values.
To expand on the perfomance argument: `i32` obviously uses half of the
memory of `i64` meaning half the memory bandwidth used, half as much
cache consumption and twice as much vectorization – additionally
arithmetic (like multiplication and division) is faster on some of the
modern CPUs.
## Case analysis
This is an analysis of cases where `int` inference might be thought of