From ad85ec765bcf3b3e501f445ab4e35169bc7576d7 Mon Sep 17 00:00:00 2001 From: gingerBill Date: Wed, 24 Sep 2025 10:21:38 +0100 Subject: [PATCH] More const union improvements --- src/llvm_backend_const.cpp | 71 ++++++++++++++++++++++++++++-------- src/llvm_backend_general.cpp | 5 ++- 2 files changed, 58 insertions(+), 18 deletions(-) diff --git a/src/llvm_backend_const.cpp b/src/llvm_backend_const.cpp index 9069f3bdf..219700ffd 100644 --- a/src/llvm_backend_const.cpp +++ b/src/llvm_backend_const.cpp @@ -542,6 +542,12 @@ gb_internal LLVMValueRef lb_construct_const_union(lbModule *m, LLVMValueRef vari GB_ASSERT(bt->kind == Type_Union); GB_ASSERT(lb_type(m, variant_type) == LLVMTypeOf(variant_value)); + LLVMTypeRef llvm_type = lb_type(m, union_type); + + if (LLVMIsNull(variant_value)) { + return LLVMConstNull(llvm_type); + } + if (bt->Union.variants.count == 0) { GB_ASSERT(LLVMIsNull(variant_value)); return variant_value; @@ -550,7 +556,6 @@ gb_internal LLVMValueRef lb_construct_const_union(lbModule *m, LLVMValueRef vari i64 block_size = bt->Union.variant_block_size; i64 variant_size = type_size_of(variant_type); - LLVMTypeRef llvm_type = lb_type(m, union_type); LLVMTypeRef llvm_variant_type = lb_type(m, variant_type); if (is_type_union_maybe_pointer(bt)) { @@ -580,13 +585,6 @@ gb_internal LLVMValueRef lb_construct_const_union(lbModule *m, LLVMValueRef vari LLVMTypeRef block_type = LLVMStructGetTypeAtIndex(llvm_type, 0); - LLVMTypeRef block_padding = nullptr; - i64 block_padding_size = block_size - variant_size; - if (block_padding_size > 0) { - block_padding = lb_type_padding_filler(m, block_padding_size, type_align_of(variant_type)); - return nullptr; - } - LLVMTypeRef tag_type = lb_type(m, union_tag_type(bt)); i64 used_size = block_size + lb_sizeof(tag_type); @@ -601,12 +599,55 @@ gb_internal LLVMValueRef lb_construct_const_union(lbModule *m, LLVMValueRef vari unsigned i = 0; LLVMValueRef values[3] = {}; - LLVMValueRef variant_value_wrapped = variant_value; + LLVMValueRef block_value = variant_value; if (lb_sizeof(llvm_variant_type) == 0) { - variant_value_wrapped = LLVMConstNull(block_type); + block_value = LLVMConstNull(block_type); } else if (block_type != llvm_variant_type) { if (block_size != variant_size) { + + if (LLVMGetTypeKind(block_type) == LLVMArrayTypeKind && + LLVMGetTypeKind(llvm_variant_type) == LLVMIntegerTypeKind) { + LLVMTypeRef elem = LLVMGetElementType(block_type); + unsigned count = LLVMGetArrayLength(block_type); + if (elem == llvm_variant_type) { + LLVMValueRef *elems = temporary_alloc_array(count); + elems[0] = variant_value; + for (unsigned j = 1; j < count; j++) { + elems[j] = LLVMConstNull(elem); + } + block_value = LLVMConstArray(elem, elems, count); + + goto assign_value_wrapped; + } else if (!is_type_different_to_arch_endianness(variant_type)) { + i64 elem_size = lb_sizeof(elem); + i64 variant_size = lb_sizeof(llvm_variant_type); + if (elem_size > variant_size) { + u64 val = LLVMConstIntGetZExtValue(variant_value); + + LLVMValueRef *elems = temporary_alloc_array(count); + elems[0] = LLVMConstInt(elem, val, false); + for (unsigned j = 1; j < count; j++) { + elems[j] = LLVMConstNull(elem); + } + block_value = LLVMConstArray(elem, elems, count); + + goto assign_value_wrapped; + } + } + } else if (LLVMGetTypeKind(block_type) == LLVMIntegerTypeKind && + LLVMGetTypeKind(llvm_variant_type) == LLVMIntegerTypeKind) { + if (!is_type_different_to_arch_endianness(variant_type)) { + i64 variant_size = lb_sizeof(llvm_variant_type); + if (block_size > variant_size) { + u64 val = LLVMConstIntGetZExtValue(variant_value); + block_value = LLVMConstInt(block_type, val, false); + + goto assign_value_wrapped; + } + } + } + return nullptr; } if (LLVMGetTypeKind(block_type) == LLVMIntegerTypeKind) { @@ -614,10 +655,10 @@ gb_internal LLVMValueRef lb_construct_const_union(lbModule *m, LLVMValueRef vari case LLVMHalfTypeKind: case LLVMFloatTypeKind: case LLVMDoubleTypeKind: - variant_value_wrapped = LLVMConstBitCast(variant_value_wrapped, block_type); + block_value = LLVMConstBitCast(block_value, block_type); goto assign_value_wrapped; case LLVMPointerTypeKind: - variant_value_wrapped = LLVMConstPtrToInt(variant_value_wrapped, block_type); + block_value = LLVMConstPtrToInt(block_value, block_type); goto assign_value_wrapped; } } @@ -626,11 +667,8 @@ gb_internal LLVMValueRef lb_construct_const_union(lbModule *m, LLVMValueRef vari } assign_value_wrapped:; - values[i++] = variant_value_wrapped; + values[i++] = block_value; - if (block_padding_size > 0) { - values[i++] = LLVMConstNull(block_padding); - } unsigned long long the_tag = cast(unsigned long long)union_variant_index(union_type, variant_type); values[i++] = LLVMConstInt(tag_type, the_tag, false); if (padding > 0) { @@ -646,6 +684,7 @@ gb_internal bool lb_try_construct_const_union(lbModule *m, lbValue *value, Type *value = {res, union_type}; return true; } + // gb_printf_err("%s -> %s\n", LLVMPrintValueToString(value->value), LLVMPrintTypeToString(lb_type(m, union_type))); } return false; } diff --git a/src/llvm_backend_general.cpp b/src/llvm_backend_general.cpp index 4c60d9f4c..6e513a075 100644 --- a/src/llvm_backend_general.cpp +++ b/src/llvm_backend_general.cpp @@ -1733,10 +1733,11 @@ gb_internal LLVMTypeRef lb_type_internal_union_block_type(lbModule *m, Type *typ } i64 align = type_align_of(type); - i64 size = type_size_of(type); - gb_unused(size); unsigned block_size = cast(unsigned)type->Union.variant_block_size; + if (block_size == 0) { + return lb_type_padding_filler(m, block_size, align); + } bool all_pointers = align == build_context.ptr_size; for (isize i = 0; all_pointers && i < type->Union.variants.count; i++) {