YJIT: Properly deal with cfunc splat when no args needed

[jimmyhmiller]

Related to:
#7377

Previously it was believed that there was a problem with a combination of cfuncs + splat + send, but it turns out the same issue happened without send. For example Integer.sqrt(1, *[]). The issue was happening not because of send, but because of setting the wrong argc when we don't need to splat any args.

[jimmyhmiller]

The failures are an rbs thing that I've seen elsewhere unrelated to this patch.

[maximecb]

Good catch Jimmy :)

[k0kubun]

I'm not sure why our CI never catches it, but it seems like this PR re-introduced the bug that was stopped by #7377.

As of a80906a, spec/ruby/library/bigdecimal/mult_spec.rb succeeds:

$ make test-spec SPECOPTS="spec/ruby/library/bigdecimal/mult_spec.rb" RUBYOPT=--yjit-call-threshold=1
make: Entering directory '/home/k0kubun/src/github.com/ruby/ruby/.ruby'
$ /home/k0kubun/src/github.com/ruby/ruby/.ruby/miniruby -I/home/k0kubun/src/github.com/ruby/ruby/lib /home/k0kubun/src/github.com/ruby/ruby/tool/runruby.rb --archdir=/home/k0kubun/src/github.com/ruby/ruby/.ruby --extout=.ext -- /home/k0kubun/src/github.com/ruby/ruby/spec/mspec/bin/mspec-run -B ../spec/default.mspec ../spec/ruby/library/bigdecimal/mult_spec.rb
ruby 3.3.0dev (2023-03-01T21:07:40Z master a80906a714) +YJIT dev [x86_64-linux]
[/ | ==================100%================== | 00:00:00]      0F      0E

Finished in 0.160945 seconds

1 file, 7 examples, 228 expectations, 0 failures, 0 errors, 0 tagged
make: Leaving directory '/home/k0kubun/src/github.com/ruby/ruby/.ruby'

In the next commit cb8a040 with this patch, it fails:

$ make test-spec SPECOPTS="spec/ruby/library/bigdecimal/mult_spec.rb" RUBYOPT=--yjit-call-threshold=1
make: Entering directory '/home/k0kubun/src/github.com/ruby/ruby/.ruby'
$ /home/k0kubun/src/github.com/ruby/ruby/.ruby/miniruby -I/home/k0kubun/src/github.com/ruby/ruby/lib /home/k0kubun/src/github.com/ruby/ruby/tool/runruby.rb --archdir=/home/k0kubun/src/github.com/ruby/ruby/.ruby --extout=.ext -- /home/k0kubun/src/github.com/ruby/ruby/spec/mspec/bin/mspec-run -B ../spec/default.mspec ../spec/ruby/library/bigdecimal/mult_spec.rb
ruby 3.3.0dev (2023-03-01T21:33:16Z master cb8a040b79) +YJIT dev [x86_64-linux]

1)
BigDecimal#mult returns zero of appropriate sign if self or argument is zero ERROR
TypeError: no implicit conversion of false into Integer
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:36:in `mult'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:36:in `block (2 levels) in <top (required)>'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/mult_spec.rb:5:in `<top (required)>'

2)
BigDecimal#mult returns NaN if NaN is involved ERROR
TypeError: no implicit conversion of false into Integer
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:54:in `mult'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:54:in `block (3 levels) in <top (required)>'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:53:in `each'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:53:in `block (2 levels) in <top (required)>'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/mult_spec.rb:5:in `<top (required)>'

3)
BigDecimal#mult returns zero if self or argument is zero ERROR
TypeError: no implicit conversion of false into Integer
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:64:in `mult'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:64:in `block (4 levels) in <top (required)>'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:63:in `each'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:63:in `block (3 levels) in <top (required)>'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:62:in `each'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:62:in `block (2 levels) in <top (required)>'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/mult_spec.rb:5:in `<top (required)>'

4)
BigDecimal#mult returns infinite value if self or argument is infinite ERROR
TypeError: no implicit conversion of false into Integer
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:78:in `mult'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:78:in `block (4 levels) in <top (required)>'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:77:in `each'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:77:in `block (3 levels) in <top (required)>'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:76:in `each'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:76:in `block (2 levels) in <top (required)>'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/mult_spec.rb:5:in `<top (required)>'

5)
BigDecimal#mult returns NaN if the result is undefined ERROR
TypeError: no implicit conversion of false into Integer
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:92:in `mult'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/shared/mult.rb:92:in `block (2 levels) in <top (required)>'
/home/k0kubun/src/github.com/ruby/ruby/spec/ruby/library/bigdecimal/mult_spec.rb:5:in `<top (required)>'
[- | ==================100%================== | 00:00:00]      0F      5E

Finished in 0.175124 seconds

1 file, 7 examples, 4 expectations, 0 failures, 5 errors, 0 tagged
make: *** [uncommon.mk:896: yes-test-spec] Error 1
make: Leaving directory '/home/k0kubun/src/github.com/ruby/ruby/.ruby'