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-rw-r--r--src/codegen/llvm.zig115
1 files changed, 104 insertions, 11 deletions
diff --git a/src/codegen/llvm.zig b/src/codegen/llvm.zig
index aa10cd4fd4..b9c8e5437f 100644
--- a/src/codegen/llvm.zig
+++ b/src/codegen/llvm.zig
@@ -764,15 +764,25 @@ pub const Object = struct {
arg_ptr.setAlignment(param_ty.abiAlignment(target));
var field_i: u32 = 0;
+ var field_offset: u32 = 0;
for (llvm_ints) |int_bits| {
const param = llvm_func.getParam(llvm_arg_i);
llvm_arg_i += 1;
const big_int_ty = dg.context.intType(int_bits);
- var bits_used: u16 = 0;
+ var bits_used: u32 = 0;
while (bits_used < int_bits) {
const field = fields[field_i];
- const field_abi_bits = @intCast(u16, field.ty.abiSize(target)) * 8;
+ const field_alignment = field.normalAlignment(target);
+ const prev_offset = field_offset;
+ field_offset = std.mem.alignForwardGeneric(u32, field_offset, field_alignment);
+ if (field_offset > prev_offset) {
+ // Padding counts as bits used.
+ bits_used += (field_offset - prev_offset) * 8;
+ if (bits_used >= int_bits) break;
+ }
+ const field_size = @intCast(u16, field.ty.abiSize(target));
+ const field_abi_bits = field_size * 8;
const field_int_ty = dg.context.intType(field_abi_bits);
const shifted = if (bits_used == 0) param else s: {
const shift_amt = big_int_ty.constInt(bits_used, .False);
@@ -782,14 +792,15 @@ pub const Object = struct {
var ty_buf: Type.Payload.Pointer = undefined;
const llvm_i = llvmFieldIndex(param_ty, field_i, target, &ty_buf).?;
const field_ptr = builder.buildStructGEP(arg_ptr, llvm_i, "");
- const field_alignment = field.normalAlignment(target);
const casted_ptr = builder.buildBitCast(field_ptr, field_int_ty.pointerType(0), "");
const store_inst = builder.buildStore(field_as_int, casted_ptr);
store_inst.setAlignment(field_alignment);
- bits_used += field_abi_bits;
field_i += 1;
if (field_i >= fields.len) break;
+
+ bits_used += field_abi_bits;
+ field_offset += field_size;
}
if (field_i >= fields.len) break;
}
@@ -2689,9 +2700,65 @@ pub const DeclGen = struct {
try llvm_params.append(dg.context.intType(abi_size * 8));
},
.multiple_llvm_ints => {
+ const param_ty = fn_info.param_types[it.zig_index - 1];
+ const llvm_ints = it.llvm_types_buffer[0..it.llvm_types_len];
try llvm_params.ensureUnusedCapacity(it.llvm_types_len);
- for (it.llvm_types_buffer[0..it.llvm_types_len]) |int_bits| {
- llvm_params.appendAssumeCapacity(dg.context.intType(int_bits));
+
+ // The reason we have all this logic instead of simply appending
+ // big_int_ty is for the special case of a pointer type;
+ // we want to use a pointer type instead of inttoptr at the callsites,
+ // which may prevent optimization.
+ switch (param_ty.zigTypeTag()) {
+ .Struct => {
+ const fields = param_ty.structFields().values();
+ var field_i: u32 = 0;
+ var field_offset: u32 = 0;
+ llvm_arg: for (llvm_ints) |int_bits| {
+ const big_int_ty = dg.context.intType(int_bits);
+ var bits_used: u32 = 0;
+ while (bits_used < int_bits) {
+ const field = fields[field_i];
+ const field_alignment = field.normalAlignment(target);
+ const prev_offset = field_offset;
+ field_offset = std.mem.alignForwardGeneric(u32, field_offset, field_alignment);
+ if (field_offset > prev_offset) {
+ // Padding counts as bits used.
+ bits_used += (field_offset - prev_offset) * 8;
+ if (bits_used >= int_bits) break;
+ }
+ const field_size = @intCast(u16, field.ty.abiSize(target));
+ const field_abi_bits = field_size * 8;
+
+ // Special case for when the entire LLVM integer represents
+ // one field; in this case keep the type information
+ // to avoid the potentially costly ptrtoint/bitcast.
+ if (bits_used == 0 and field_abi_bits == int_bits) {
+ const llvm_field_ty = try dg.llvmType(field.ty);
+ llvm_params.appendAssumeCapacity(llvm_field_ty);
+ field_i += 1;
+ if (field_i >= fields.len) {
+ break :llvm_arg;
+ } else {
+ continue :llvm_arg;
+ }
+ }
+
+ field_i += 1;
+ if (field_i >= fields.len) break;
+
+ bits_used += field_abi_bits;
+ field_offset += field_size;
+ }
+ llvm_params.appendAssumeCapacity(big_int_ty);
+ if (field_i >= fields.len) break;
+ }
+ },
+ else => {
+ for (llvm_ints) |int_bits| {
+ const big_int_ty = dg.context.intType(int_bits);
+ llvm_params.appendAssumeCapacity(big_int_ty);
+ }
+ },
}
},
};
@@ -4070,22 +4137,46 @@ pub const FuncGen = struct {
.Struct => {
const fields = param_ty.structFields().values();
var field_i: u32 = 0;
+ var field_offset: u32 = 0;
for (llvm_ints) |int_bits| {
const big_int_ty = self.dg.context.intType(int_bits);
var int_arg: *const llvm.Value = undefined;
- var bits_used: u16 = 0;
+ var bits_used: u32 = 0;
while (bits_used < int_bits) {
const field = fields[field_i];
+ const field_alignment = field.normalAlignment(target);
+ const prev_offset = field_offset;
+ field_offset = std.mem.alignForwardGeneric(u32, field_offset, field_alignment);
+ if (field_offset > prev_offset) {
+ // Padding counts as bits used.
+ bits_used += (field_offset - prev_offset) * 8;
+ if (bits_used >= int_bits) break;
+ }
var ty_buf: Type.Payload.Pointer = undefined;
const llvm_i = llvmFieldIndex(param_ty, field_i, target, &ty_buf).?;
- const field_abi_bits = @intCast(u16, field.ty.abiSize(target)) * 8;
+ const field_size = @intCast(u16, field.ty.abiSize(target));
+ const field_abi_bits = field_size * 8;
+
+ // Special case for when the entire LLVM integer represents
+ // one field; in this case keep the type information
+ // to avoid the potentially costly ptrtoint/bitcast.
+ if (bits_used == 0 and field_abi_bits == int_bits) {
+ int_arg = if (is_by_ref) f: {
+ const field_ptr = self.builder.buildStructGEP(llvm_arg, llvm_i, "");
+ const load_inst = self.builder.buildLoad(field_ptr, "");
+ load_inst.setAlignment(field_alignment);
+ break :f load_inst;
+ } else self.builder.buildExtractValue(llvm_arg, llvm_i, "");
+ field_i += 1;
+ break;
+ }
+
const field_int_ty = self.dg.context.intType(field_abi_bits);
const llvm_field = if (is_by_ref) f: {
const field_ptr = self.builder.buildStructGEP(llvm_arg, llvm_i, "");
- const alignment = field.normalAlignment(target);
const casted_ptr = self.builder.buildBitCast(field_ptr, field_int_ty.pointerType(0), "");
const load_inst = self.builder.buildLoad(casted_ptr, "");
- load_inst.setAlignment(alignment);
+ load_inst.setAlignment(field_alignment);
break :f load_inst;
} else f: {
const llvm_field = self.builder.buildExtractValue(llvm_arg, llvm_i, "");
@@ -4101,9 +4192,11 @@ pub const FuncGen = struct {
int_arg = self.builder.buildOr(int_arg, shifted, "");
}
- bits_used += field_abi_bits;
field_i += 1;
if (field_i >= fields.len) break;
+
+ bits_used += field_abi_bits;
+ field_offset += field_size;
}
llvm_args.appendAssumeCapacity(int_arg);
if (field_i >= fields.len) break;
generated by cgit v1.2.3 (git 2.39.1) at 2025-12-28 07:36:23 +0000