• Adam D. Ruppe (8/8) Aug 23 2020 A little known fact is dmd actually provides index and length for
• kinke (6/15) Aug 23 2020 Such hacks don't work with LDC and its strongly typed IR, so we
• kinke (1/1) Aug 23 2020 [e2ir.d is part of DMD's glue layer, not included by LDC.]
• Adam D. Ruppe (5/11) Aug 23 2020 Blargh.
• Kagamin (3/5) Aug 27 2020 Just call the extended function _d_arraybounds2 and you can live
• David Nadlinger (14/16) Aug 23 2020 Use grep. :P

Adam D. Ruppe <destructionator gmail.com> writes:

A little known fact is dmd actually provides index and length for 
RangeError in e2ir.d, but druntime doesn't do anything with it.

I just tried defining an object.d in ldc with this:

extern(C) void _d_arraybounds(string file, size_t line, size_t 
lwr, size_t upr, size_t length) {}


to take advantage of this data and ldc outright rejected it. I 
don't really know my way around the ldc source... what can I do 
about this?

kinke <noone nowhere.com> writes:

On Sunday, 23 August 2020 at 13:25:30 UTC, Adam D. Ruppe wrote:
 A little known fact is dmd actually provides index and length 
 for RangeError in e2ir.d, but druntime doesn't do anything with 
 it.

 I just tried defining an object.d in ldc with this:

 extern(C) void _d_arraybounds(string file, size_t line, size_t 
 lwr, size_t upr, size_t length) {}


 to take advantage of this data and ldc outright rejected it. I 
 don't really know my way around the ldc source... what can I do 
 about this?

Such hacks don't work with LDC and its strongly typed IR, so we 
don't pass these unused extra args. You can grep the src for 
`_d_arraybounds`, adjusting the signature of this runtime hook 
and the call site in DtoBoundsCheckFailCall(), but will have to 
adapt more code to forward the extra args to the latter function.

kinke <noone nowhere.com> writes:

[e2ir.d is part of DMD's glue layer, not included by LDC.]

Adam D. Ruppe <destructionator gmail.com> writes:

On Sunday, 23 August 2020 at 13:41:18 UTC, kinke wrote:
 Such hacks don't work with LDC and its strongly typed IR, so we 
 don't pass these unused extra args. You can grep the src for 
 `_d_arraybounds`, adjusting the signature of this runtime hook 
 and the call site in DtoBoundsCheckFailCall(), but will have to 
 adapt more code to forward the extra args to the latter 
 function.

Blargh.

I plan to get that info used in upstream dmd druntime eventually, 
but meh I'll keep living in darkness for now.

oh well

Kagamin <spam here.lot> writes:

On Sunday, 23 August 2020 at 14:19:13 UTC, Adam D. Ruppe wrote:
 I plan to get that info used in upstream dmd druntime 
 eventually, but meh I'll keep living in darkness for now.

Just call the extended function _d_arraybounds2 and you can live 
with both.

"David Nadlinger" <code klickverbot.at> writes:

On 23 Aug 2020, at 14:25, Adam D. Ruppe via digitalmars-d-ldc wrote:
 I don't really know my way around the ldc source... what can I do 
 about this?

Use grep. :P

---

~/ldc $ rg arraybounds
gen/runtime.cpp
554:  // void _d_arraybounds(string file, uint line)
555:  createFwdDecl(LINKc, Type::tvoid, {"_d_assert", "_d_arraybounds"},

gen/arrays.cpp
1365:        getRuntimeFunction(loc, irs->module, "_d_arraybounds");
---

You can add the extra parameters in gen/runtime.cpp (first hit), but 
you'll also need to update the bounds checking code to emit the extra 
argument (second hit).

  — David