shishantbiswas/c3c
1
1
Fork 0
mirror of https://github.com/c3lang/c3c.git synced 2026-02-27 12:01:16 +00:00
Code Issues Packages Projects Releases Wiki Activity

Fixes to bitstruct.

Browse Source
This commit is contained in:
Christoffer Lerno
2022-08-14 01:06:00 +02:00
parent b72718ba2a
commit 63d9853bd3
10 changed files with 854 additions and 89 deletions
Download Patch File Download Diff File Expand all files Collapse all files

83
src/compiler/llvm_codegen_expr.c
View File

@@ -18,6 +18,7 @@ static void llvm_emit_initialize_designated(GenContext *c, BEValue *ref, AlignSi
static inline void llvm_emit_const_initialize_reference(GenContext *c, BEValue *ref, Expr *expr);
static inline void llvm_emit_initialize_reference(GenContext *c, BEValue *ref, Expr *expr);
static void llvm_convert_vector_comparison(GenContext *c, BEValue *be_value, LLVMValueRef val, Type *vector_type);
static bool bitstruct_requires_bitswap(Decl *decl);
BEValue llvm_emit_assign_expr(GenContext *c, BEValue *ref, Expr *expr, LLVMValueRef failable)
{
@@ -207,7 +208,7 @@ LLVMValueRef llvm_mask_low_bits(GenContext *c, LLVMValueRef value, unsigned low_
BitSize type_bits = llvm_bitsize(c, type);
if (type_bits <= low_bits) return value;
LLVMValueRef mask = llvm_emit_lshr_fixed(c, llvm_get_ones_raw(type), type_bits - low_bits);
return LLVMBuildAnd(c->builder, mask, value, "");
return llvm_emit_and_raw(c, mask, value);
}
LLVMTypeRef llvm_const_padding_type(GenContext *c, AlignSize size)
@@ -743,9 +744,7 @@ static inline void llvm_extract_bitvalue_from_array(GenContext *c, BEValue *be_v
llvm_extract_bool_bit_from_array(c, be_value, member);
return;
}
bool big_endian = platform_target.big_endian;
if (parent_decl->bitstruct.big_endian) big_endian = true;
if (parent_decl->bitstruct.little_endian) big_endian = false;
bool bswap = bitstruct_requires_bitswap(parent_decl);
unsigned start = member->var.start_bit;
unsigned end = member->var.end_bit;
LLVMValueRef array_ptr = be_value->value;
@@ -780,9 +779,9 @@ static inline void llvm_extract_bitvalue_from_array(GenContext *c, BEValue *be_v
continue;
}
if (!llvm_is_const_null(element)) res = LLVMBuildOr(c->builder, element, res, "");
res = llvm_emit_or_raw(c, element, res);
}
if (big_endian)
if (bswap)
{
res = llvm_bswap_non_integral(c, res, end - start + 1);
}
@@ -812,12 +811,8 @@ static inline void llvm_extract_bitvalue(GenContext *c, BEValue *be_value, Expr
llvm_extract_bitvalue_from_array(c, be_value, member, parent_decl);
return;
}
bool bswap = false;
if (parent_decl->bitstruct.big_endian && !platform_target.big_endian) bswap = true;
if (parent_decl->bitstruct.little_endian && platform_target.big_endian) bswap = true;
LLVMValueRef value = llvm_load_value_store(c, be_value);
if (bswap) value = llvm_emit_bswap(c, value);
LLVMTypeRef container_type = LLVMTypeOf(value);
if (bitstruct_requires_bitswap(parent_decl)) value = llvm_emit_bswap(c, value);
BitSize container_size = type_size(be_value->type);
BitSize container_bit_size = container_size * 8;
unsigned start = (unsigned)member->var.start_bit;
@@ -882,18 +877,16 @@ static inline void llvm_emit_bitassign_array(GenContext *c, BEValue *result, BEV
LLVMValueRef byte_ptr = llvm_emit_array_gep_raw(c, array_ptr, array_type, start_bit / 8, parent.alignment, &alignment);
LLVMValueRef current = llvm_load(c, c->byte_type, byte_ptr, alignment, "");
LLVMValueRef bit = llvm_emit_shl_fixed(c, LLVMConstInt(c->byte_type, 1, 0), start_bit % 8);
current = LLVMBuildAnd(c->builder, current, LLVMBuildNot(c->builder, bit, ""), "");
if (!llvm_is_const_null(value)) current = LLVMBuildOr(c->builder, current, value, "");
current = llvm_emit_and_raw(c, current, LLVMBuildNot(c->builder, bit, ""));
current = llvm_emit_or_raw(c, current, value);
llvm_store_to_ptr_raw_aligned(c, byte_ptr, current, alignment);
return;
}
bool big_endian = platform_target.big_endian;
if (parent_decl->bitstruct.big_endian) big_endian = true;
if (parent_decl->bitstruct.little_endian) big_endian = false;
bool need_bitswap = bitstruct_requires_bitswap(parent_decl);
unsigned bit_size = end_bit - start_bit + 1;
if (big_endian)
if (need_bitswap)
{
value = llvm_bswap_non_integral(c, value, bit_size);
}
@@ -924,15 +917,15 @@ static inline void llvm_emit_bitassign_array(GenContext *c, BEValue *result, BEV
// We might need to mask the top bits
if (i == end_byte && end_mod != 7)
{
res = LLVMBuildAnd(c->builder, res, llvm_const_low_bitmask(c, c->byte_type, 8, end_mod + 1), "");
mask = LLVMBuildOr(c->builder, mask, llvm_const_high_bitmask(c, c->byte_type, 8, 7 - (int)end_bit), "");
res = llvm_emit_and_raw(c, res, llvm_const_low_bitmask(c, c->byte_type, 8, end_mod + 1));
mask = llvm_emit_or_raw(c, mask, llvm_const_high_bitmask(c, c->byte_type, 8, 7 - (int)end_bit));
}
// Load the current value.
LLVMValueRef current = llvm_load(c, c->byte_type, byte_ptr, alignment, "");
// Empty the top bits.
current = LLVMBuildAnd(c->builder, current, mask, "");
current = llvm_emit_and_raw(c, current, mask);
// Use *or* with the top bits from "res":
if (!llvm_is_const_null(res)) current = LLVMBuildOr(c->builder, current, res, "");
current = llvm_emit_or_raw(c, current, res);
// And store it back.
llvm_store_to_ptr_raw_aligned(c, byte_ptr, current, alignment);
// We now shift the value by the number of bits we used.
@@ -946,13 +939,13 @@ static inline void llvm_emit_bitassign_array(GenContext *c, BEValue *result, BEV
value = llvm_zext_trunc(c, value, c->byte_type);
// Create a mask for the lower bits.
LLVMValueRef mask = llvm_const_low_bitmask(c, c->byte_type, 8, end_mod + 1);
value = LLVMBuildAnd(c->builder, value, mask, "");
value = llvm_emit_and_raw(c, value, mask);
// Load the current value.
LLVMValueRef current = llvm_load(c, c->byte_type, byte_ptr, alignment, "");
// Clear the lower bits.
current = LLVMBuildAnd(c->builder, current, LLVMBuildNot(c->builder, mask, ""), "");
current = llvm_emit_and_raw(c, current, LLVMBuildNot(c->builder, mask, ""));
// Use *or* with the bottom bits from "value":
if (!llvm_is_const_null(value)) current = LLVMBuildOr(c->builder, current, value, "");
llvm_emit_or_raw(c, current, value);
// And store it back.
llvm_store_to_ptr_raw_aligned(c, byte_ptr, current, alignment);
continue;
@@ -989,15 +982,17 @@ static inline void llvm_emit_bitassign_expr(GenContext *c, BEValue *be_value, Ex
llvm_emit_expr(c, be_value, exprptr(expr->binary_expr.right));
}
if (type_lowering(parent_expr->type)->type_kind == TYPE_ARRAY)
Type *parent_type = type_flatten_distinct(parent_expr->type);
if (type_lowering(parent_type)->type_kind == TYPE_ARRAY)
{
llvm_emit_bitassign_array(c, be_value, parent, type_flatten_distinct(parent_expr->type)->decl, member);
llvm_emit_bitassign_array(c, be_value, parent, parent_type->decl, member);
return;
}
// To start the assign, pull out the current value.
LLVMValueRef current_value = llvm_load_value_store(c, &parent);
bool bswap = bitstruct_requires_bitswap(parent_type->decl);
if (bswap) current_value = llvm_emit_bswap(c, current_value);
// Get the type.
LLVMTypeRef struct_type = LLVMTypeOf(current_value);
@@ -1021,10 +1016,11 @@ static inline void llvm_emit_bitassign_expr(GenContext *c, BEValue *be_value, Ex
// Shift to the correct location.
value = llvm_emit_shl_fixed(c, value, start_bit);
// And combine using ((current_value & ~mask) | (value & mask))
value = LLVMBuildAnd(c->builder, value, mask, "");
current_value = LLVMBuildAnd(c->builder, current_value, LLVMBuildNot(c->builder, mask, ""), "");
value = llvm_emit_and_raw(c, value, mask);
current_value = llvm_emit_and_raw(c, current_value, LLVMBuildNot(c->builder, mask, ""));
// Skip this op for LLVM14 if zero.
if (!llvm_is_const_null(value)) current_value = LLVMBuildOr(c->builder, current_value, value, "");
current_value = llvm_emit_or_raw(c, current_value, value);
if (bswap) current_value = llvm_emit_bswap(c, current_value);
llvm_store_raw(c, &parent, current_value);
}
static inline void llvm_emit_bitaccess(GenContext *c, BEValue *be_value, Expr *expr)
@@ -1693,13 +1689,18 @@ static inline void llvm_emit_initialize_reference_designated(GenContext *c, BEVa
#define MAX_AGG 16
static bool bitstruct_requires_bitswap(Decl *decl)
{
bool big_endian = platform_target.big_endian;
if (decl->bitstruct.big_endian) return !big_endian;
if (decl->bitstruct.little_endian) return big_endian;
return false;
}
LLVMValueRef llvm_emit_const_bitstruct_array(GenContext *c, ConstInitializer *initializer)
{
Decl *decl = initializer->type->decl;
Type *base_type = decl->bitstruct.base_type->type;
bool big_endian = platform_target.big_endian;
if (decl->bitstruct.big_endian) big_endian = true;
if (decl->bitstruct.little_endian) big_endian = false;
unsigned elements = base_type->array.len;
LLVMValueRef stack_data[MAX_AGG];
LLVMValueRef* slots = elements > MAX_AGG ? MALLOC(elements * sizeof(LLVMValueRef)) : stack_data;
@@ -1730,7 +1731,7 @@ LLVMValueRef llvm_emit_const_bitstruct_array(GenContext *c, ConstInitializer *in
LLVMValueRef bit = llvm_emit_shl_fixed(c, LLVMConstInt(c->byte_type, 1, 0), start_bit % 8);
unsigned byte = start_bit / 8;
LLVMValueRef current_value = slots[byte];
slots[byte] = LLVMBuildOr(c->builder, current_value, bit, "");
slots[byte] = llvm_emit_or_raw(c, current_value, bit);
continue;
}
unsigned bit_size = end_bit - start_bit + 1;
@@ -1743,7 +1744,7 @@ LLVMValueRef llvm_emit_const_bitstruct_array(GenContext *c, ConstInitializer *in
int end_byte = end_bit / 8;
ByteSize member_type_bitsize = type_size(member_type) * 8;
value = llvm_mask_low_bits(c, value, bit_size);
if (big_endian && bit_size > 8)
if (bitstruct_requires_bitswap(decl) && bit_size > 8)
{
value = llvm_bswap_non_integral(c, value, bit_size);
}
@@ -1765,7 +1766,7 @@ LLVMValueRef llvm_emit_const_bitstruct_array(GenContext *c, ConstInitializer *in
}
if (member_type_bitsize > 8) to_or = LLVMBuildTrunc(c->builder, to_or, c->byte_type, "");
LLVMValueRef current_value = slots[(unsigned)j];
slots[(unsigned)j] = LLVMBuildOr(c->builder, to_or, current_value, "");
slots[(unsigned)j] = llvm_emit_or_raw(c, to_or, current_value);
}
}
return llvm_get_array(c->byte_type, slots, elements);
@@ -1811,19 +1812,15 @@ LLVMValueRef llvm_emit_const_bitstruct(GenContext *c, ConstInitializer *initiali
if (bit_size < base_type_bitsize)
{
LLVMValueRef mask = llvm_emit_lshr_fixed(c, llvm_get_ones_raw(llvm_base_type), base_type_bitsize - bit_size);
value = LLVMBuildAnd(c->builder, mask, value, "");
value = llvm_emit_and_raw(c, mask, value);
}
if (start_bit > 0)
{
value = llvm_emit_shl_fixed(c, value, start_bit);
}
result = LLVMBuildOr(c->builder, value, result, "");
result = llvm_emit_or_raw(c, value, result);
}
if (decl->bitstruct.little_endian && platform_target.big_endian)
{
return LLVMConstBswap(result);
}
if (decl->bitstruct.big_endian && !platform_target.big_endian)
if (bitstruct_requires_bitswap(decl))
{
return LLVMConstBswap(result);
}