enum ABIArgInfo::Kind
Declared at: clang/include/clang/CodeGen/CGFunctionInfo.h:34
Enumerators
| Name | Value | Comment |
|---|---|---|
| Direct | 0 | Direct - Pass the argument directly using the normal converted LLVM type, or by coercing to another specified type stored in 'CoerceToType'). If an offset is specified (in UIntData), then the argument passed is offset by some number of bytes in the memory representation. A dummy argument is emitted before the real argument if the specified type stored in "PaddingType" is not zero. |
| Extend | 1 | Extend - Valid only for integer argument types. Same as 'direct' but also emit a zero/sign extension attribute. |
| Indirect | 2 | Indirect - Pass the argument indirectly via a hidden pointer with the specified alignment (0 indicates default alignment) and address space. |
| IndirectAliased | 3 | IndirectAliased - Similar to Indirect, but the pointer may be to an object that is otherwise referenced. The object is known to not be modified through any other references for the duration of the call, and the callee must not itself modify the object. Because C allows parameter variables to be modified and guarantees that they have unique addresses, the callee must defensively copy the object into a local variable if it might be modified or its address might be compared. Since those are uncommon, in principle this convention allows programs to avoid copies in more situations. However, it may introduce *extra* copies if the callee fails to prove that a copy is unnecessary and the caller naturally produces an unaliased object for the argument. |
| Ignore | 4 | Ignore - Ignore the argument (treat as void). Useful for void and empty structs. |
| Expand | 5 | Expand - Only valid for aggregate argument types. The structure should be expanded into consecutive arguments for its constituent fields. Currently expand is only allowed on structures whose fields are all scalar types or are themselves expandable types. |
| CoerceAndExpand | 6 | CoerceAndExpand - Only valid for aggregate argument types. The structure should be expanded into consecutive arguments corresponding to the non-array elements of the type stored in CoerceToType. Array elements in the type are assumed to be padding and skipped. |
| InAlloca | 7 | InAlloca - Pass the argument directly using the LLVM inalloca attribute. This is similar to indirect with byval, except it only applies to arguments stored in memory and forbids any implicit copies. When applied to a return type, it means the value is returned indirectly via an implicit sret parameter stored in the argument struct. |
| KindFirst | 0 | InAlloca - Pass the argument directly using the LLVM inalloca attribute. This is similar to indirect with byval, except it only applies to arguments stored in memory and forbids any implicit copies. When applied to a return type, it means the value is returned indirectly via an implicit sret parameter stored in the argument struct. |
| KindLast | 7 | InAlloca - Pass the argument directly using the LLVM inalloca attribute. This is similar to indirect with byval, except it only applies to arguments stored in memory and forbids any implicit copies. When applied to a return type, it means the value is returned indirectly via an implicit sret parameter stored in the argument struct. |