memory layout and add a SelectInst API that allows for one to access select inst
operands when one does not care about what the cases actually are.
Previously select_enum, select_enum_addr had the following memory layout:
[operands], [cases]
In constrast, select_value had the following layout:
[operand1, case1, operand2, case 2, ...]
The layout for select_value makes it impossible to just visit operands in a
generic way via a higher level API. This is an important operation for many
analyses such as AA on select insts.
This commit does the following:
1. Adds a new abstract parent class for all select instructions called
SelectInst.
2. Adds a new templated implementation parent class that inherits from
SelectInst called SelectInstBase. This handles the complete implementation of
select for all types by templating on CaseTy.
3. Changes SelectEnumAddrInst, SelectEnumInst, SelectValueInst to be thin
classes that inherit from the appropriately specialized SelectInstBase.
I left in SelectEnumInstBase for now as a subclass of SelectInstBase and parent
class of SelectEnum{,Addr}Inst since it provides specific enum APIs that are
used all over the compiler. All of these methods have equivalent methods on
SelectInstBase. I just want to leave them for a later commit so that this commit
stays small.
Swift SVN r24159
We want to be able to work around problems with non-failable
Objective-C initializers actually failing, which can happen when the
API audit data incorrectly marks an initializer as non-failable.
Swift SVN r21711
An unsafe cast from a base to a derived class isn't really all that different from one from Builtin.NativeObject to an arbitrary class, so relax this pair of instructions to allow an arbitrary bitcast. This only combines the instructions; it doesn't attempt to simplify any codegen that was emitting round-trip casts before yet.
Swift SVN r16736
It's not forming the metatype for the protocol type (exists t: P. t).metatype, it's forming the existential of a metatype of a conforming type, exists t: P. (t.metatype).
Swift SVN r14520
Having one instruction to get the dynamic metatype of a (non-existential) value makes more sense from a generic specialization standpoint and should stave off inevitable crashers when archetype_metatypes get specialized. protocol_metatype remains separate because metatype existentials are more interesting.
Swift SVN r14499
We were wantonly applying 'upcast' to archetypes in some cases, and really, that's OK, since these instructions do the same thing (and generic specialization could turn archetype_ref_to_super into upcast). Make everyone's life easier by folding archetype_to_super into upcast. Fixes <rdar://problem/16192324>.
Swift SVN r14496
Split 'destructive_switch_enum_addr' into separate 'switch_enum_addr' and 'take_enum_data_addr' instructions. This should unblock some optimization work we would like to do with enums.
Swift SVN r12015
Emphasize the fact that this address is only intended for initialization. When we split destructive_switch_enum_addr, there will be another similar instruction for destructively taking the payload out of an already-initialized enum.
Swift SVN r12000
Remove the initialize_var instruction now that DI fully diagnoses initialization problems. Change String-to-NSString bridging to explicitly invoke String's default constructor; it was the last remaining user of initialize_var. Remove dead code to emit an implicit default constructor without a body.
Swift SVN r11066
