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digitalmars.D.ldc - New expression in ToElemVisitor

reply Jacob Carlborg <doob me.com> writes:
I'm adding support for a new expression to `ToElemVisitor`. It 
seems like I need to create a `DValue`, which seems to require a 
`llvm::Global` and a D type. I have the `llvm::Global` but not 
the D type. The global is created by the compiler. Any 
ideas/hints?

--
/Jacob Carlborg
Aug 20 2018
parent reply kinke <kinke libero.it> writes:
On Monday, 20 August 2018 at 07:52:31 UTC, Jacob Carlborg wrote:

 I'm adding support for a new expression to `ToElemVisitor`. It 
 seems like I need to create a `DValue`, which seems to require 
 a `llvm::Global` and a D type. I have the `llvm::Global` but 
 not the D type. The global is created by the compiler. Any 
 ideas/hints?


Yeah, results of expressions are DValues, an association of an 
arbitrary llvm::Value* (not just globals) with a D type. Not 
having a D type wasn't an issue until now, as all expressions 
have one (Expression::type); why is yours special? - As it's a 
global (presumably ObjC stuff), you could probably get away with 
a void ptr.
Aug 20 2018
parent reply Jacob Carlborg <doob me.com> writes:
On Monday, 20 August 2018 at 09:35:04 UTC, kinke wrote:


 Yeah, results of expressions are DValues, an association of an 
 arbitrary llvm::Value* (not just globals) with a D type. Not 
 having a D type wasn't an issue until now, as all expressions 
 have one (Expression::type); why is yours special? - As it's a 
 global (presumably ObjC stuff)


Yes, it's for Objective-C, as we discussed earlier [1]. I've 
created the type for the Value like Clang does, using 
`StructType::create()`.


 global (presumably ObjC stuff), you could probably get away 
 with a void ptr.


You mean an instance of `TypePointer`?

[1] 
https://forum.dlang.org/thread/slflfkzldrtzagqpihgb forum.dlang.org

--
/Jacob Carlborg
Aug 20 2018
next sibling parent reply kinke <kinke libero.it> writes:
On Monday, 20 August 2018 at 11:30:15 UTC, Jacob Carlborg wrote:

 You mean an instance of `TypePointer`?


Something like `DImValue(Type::tvoidptr, DtoBitCast(myLLGlobal, 
getVoidPtrType())` (a DLValue would be preferrable, but you'd 
probably need a proper D type then). But what's the type of your 
new Expression? Do you have some code to show?
Aug 20 2018
parent Jacob Carlborg <doob me.com> writes:
On 2018-08-20 14:03, kinke wrote:

 On Monday, 20 August 2018 at 11:30:15 UTC, Jacob Carlborg wrote:

 You mean an instance of `TypePointer`?


 
 Something like `DImValue(Type::tvoidptr, DtoBitCast(myLLGlobal, 
 getVoidPtrType())` (a DLValue would be preferrable, but you'd probably 
 need a proper D type then). But what's the type of your new Expression? 
 Do you have some code to show?


Not in LDC, yet, but in DMD. The new expression is defined here [1], 
getRuntimeMetaclass here [2] and setMetaclass here [3]. This is the code 
returning the elem value of the expression [4]. getClassReference is 
defined here [5].

[1] 
https://github.com/dlang/dmd/blob/3d289d3ea100bda6a2b25c5e43779d7dd487281f/src/dmd/expression.d#L6500-L6515

[2] 
https://github.com/dlang/dmd/blob/3d289d3ea100bda6a2b25c5e43779d7dd487281f/src/dmd/objc.d#L427-L438

[3] 
https://github.com/dlang/dmd/blob/3d289d3ea100bda6a2b25c5e43779d7dd487281f/src/dmd/objc.d#L485-L528

[4] 
https://github.com/dlang/dmd/blob/3d289d3ea100bda6a2b25c5e43779d7dd487281f/src/dmd/objc_glue.d#L143-L146

[5] 
https://github.com/dlang/dmd/blob/3d289d3ea100bda6a2b25c5e43779d7dd487281f/src/dmd/objc_glue.d#L449-L479

-- 
/Jacob Carlborg
Aug 22 2018
prev sibling parent reply kinke <noone nowhere.com> writes:
On Monday, 20 August 2018 at 11:30:15 UTC, Jacob Carlborg wrote:

 Yes, it's for Objective-C, as we discussed earlier [1].


Glancing over the original thread again, you could probably 
tackle this differently. What about defining the `_class_t` 
struct and its helper structs in object.d and stashing away that 
type (just like `Type::dtypeinfo` etc.), so that you can use it 
later for defining the ObjC global (and presumably also for your 
<NewExpression>::type)?
Aug 20 2018
parent Jacob Carlborg <doob me.com> writes:
On 2018-08-20 22:30, kinke wrote:


 Glancing over the original thread again, you could probably tackle this 
 differently. What about defining the `_class_t` struct and its helper 
 structs in object.d and stashing away that type (just like 
 `Type::dtypeinfo` etc.), so that you can use it later for defining the 
 ObjC global (and presumably also for your <NewExpression>::type)?


I guess I could. But DMD doesn't require these types, what it seems like.

-- 
/Jacob Carlborg
Aug 22 2018