get rid of structs

alex-s168 · Jan 7, 2025 · 9b484e1 · 9b484e1
1 parent aca087b
commit 9b484e1
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Showing 7 changed files with 7 additions and 47 deletions.
diff --git a/README.md b/README.md
@@ -18,7 +18,7 @@ VXCC is licenced under the [permissive Apache 2.0 license with LLVM Exceptions](
 - easy to implement code generation for any architecture
 - make it easy for people to learn about compiler backends
 - good-ish optimizations
-- beat QBE
+- beat QBE in terms of generated code speed
 
 ## **non**-goals
 - reach complexity of GCC or even LLVM
@@ -33,7 +33,6 @@ VXCC is licenced under the [permissive Apache 2.0 license with LLVM Exceptions](
 | x86 codegen                             | ![#33cc33](https://placehold.co/15x15/33cc33/33cc33.png) | done but will be re-made |
 | codegen of basic code involving loops   | ![#33cc33](https://placehold.co/15x15/33cc33/33cc33.png) | done    |
 | basic optimizations                     | ![#33cc33](https://placehold.co/15x15/33cc33/33cc33.png) | done    |
-| struct support                          | ![#ff9900](https://placehold.co/15x15/ff9900/ff9900.png) | soon    |
 | proper register allocator & ISEL rework | ![#ff9900](https://placehold.co/15x15/ff9900/ff9900.png) | soon    |
 | floating point numbers                  | ![#cc0000](https://placehold.co/15x15/cc0000/cc0000.png) | planned |
 

diff --git a/build_c b/build_c
diff --git a/frontend_dev_doc.md b/frontend_dev_doc.md
@@ -99,5 +99,9 @@ You should never use these operations:
 - `GOTO`, `COND`: using these disables a lot of optimizations.
 - `TAILCALL`: just always use `CALL` instead
 
+Structs are currently not handled by VXCC, which means that like in LLVM, you have to take care of struct calling conventions yourself (if you need them).
+You don't need those for most (if not all) C standard library functions, because they only apply if you pass or return a struct by value.
+If you don't need them for linking with existing C code, you can just "invent" your own calling convention for structs, like passing all members as arguments.
+
 ## Step 6: compile the CU 
-See `vx_CU_compile()`. Note however, that object file output is not yet implemented.
+See `vx_CU_compile()`. Note however, that object file output currently requires `nasm` in the `PATH`.
diff --git a/ir/dump.c b/ir/dump.c
@@ -25,7 +25,6 @@ const char *vx_IrName_str[VX_IR_NAME__LAST] = {
 
     [VX_IR_NAME_ID] = "id",
     [VX_IR_NAME_TYPE] = "type",
-    [VX_IR_NAME_STRUCT] = "struct",
 };
 
 void vx_IrValue_dump(vx_IrValue value, FILE *out, const size_t indent) {

diff --git a/ir/ir.c b/ir/ir.c
@@ -115,12 +115,6 @@ size_t vx_IrType_size(vx_CU* cu, vx_IrBlock* inCtx, vx_IrType *ty) {
     case VX_IR_TYPE_KIND_BASE:
         return ty->base.size;
 
-    case VX_IR_TYPE_KIND_CIR_STRUCT:
-        for (size_t i = 0; i < ty->cir_struct.members_len; i ++) {
-            total += vx_IrType_size(cu, inCtx, ty->cir_struct.members[i]);
-        }
-        return total;
-
     case VX_IR_TYPE_FUNC:
         return vx_IrType_size(cu, inCtx, cu->info.get_ptr_ty(cu, inCtx));
 

diff --git a/ir/ir.h b/ir/ir.h
@@ -70,15 +70,6 @@ static const char * vx_OptIrVar_debug(vx_OptIrVar var) {
 
 typedef struct vx_IrType_s vx_IrType;
 
-// only in C IR
-typedef struct {
-    vx_IrType **members;
-    size_t      members_len;
-
-    bool pack;
-    size_t align;
-} vx_IrTypeCIRStruct;
-
 typedef struct {
     bool   sizeless;
     size_t size;
@@ -95,9 +86,6 @@ typedef struct {
 } vx_IrTypeFunc;
 
 typedef enum {
-    // present in: cir
-    VX_IR_TYPE_KIND_CIR_STRUCT,
-
     // present in: cir, ssa
     VX_IR_TYPE_KIND_BASE,
     VX_IR_TYPE_FUNC,
@@ -110,7 +98,6 @@ struct vx_IrType_s {
 
     union {
         vx_IrTypeBase       base;
-        vx_IrTypeCIRStruct  cir_struct;
         vx_IrTypeFunc       func;
     };
 };
@@ -437,7 +424,6 @@ typedef enum {
     VX_IR_NAME_LOOP_STRIDE,
 
     VX_IR_NAME_IDX,
-    VX_IR_NAME_STRUCT,
     VX_IR_NAME_TYPE,
     VX_IR_NAME_ELSIZE,
     VX_IR_NAME_OFF,

diff --git a/ir/ops.cdef b/ir/ops.cdef
@@ -666,28 +666,6 @@ enum_entry_prefix "VX_IR_OP_"
                          sideEffect false
                          ;
 
-    entry GETELEM        args       "struct: struct var, idx: index of member"
-                         debug      "getelem"
-                         descr      "get element from struct"
-                         inlineCost 2
-                         execCost   2
-                         endsFlow   false
-                         hasEffect  true 
-                         volatile   false 
-                         sideEffect false 
-                         ;
-
-    entry SETELEM        args       "struct: old struct var, idx: index of member, val: new value of member"
-                         debug      "setelem"
-                         descr      "set element from struct by returning a struct with the modified values"
-                         inlineCost 2
-                         execCost   2
-                         endsFlow   false 
-                         hasEffect  true 
-                         volatile   false
-                         sideEffect false 
-                         ;
-
     entry IF             args       "cond: ()->bool, then: ()->R, (else: ()->R)"
                          debug      "if"
                          descr      "if"