Append disabled LLVM CPU features after enabled ones

This commit is contained in:
Shawn Gao 2024-09-23 15:08:58 -07:00 committed by Alex Rønne Petersen
parent acba2645f7
commit dafe1a910d

View File

@ -312,18 +312,29 @@ pub fn create(arena: Allocator, options: CreateOptions) !*Package.Module {
if (!options.global.use_llvm) break :b null;
var buf = std.ArrayList(u8).init(arena);
for (target.cpu.arch.allFeaturesList(), 0..) |feature, index_usize| {
const index = @as(std.Target.Cpu.Feature.Set.Index, @intCast(index_usize));
const is_enabled = target.cpu.features.isEnabled(index);
var disabled_features = std.ArrayList(u8).init(arena);
defer disabled_features.deinit();
// Append disabled features after enabled ones, so that their effects aren't overwritten.
for (target.cpu.arch.allFeaturesList()) |feature| {
if (feature.llvm_name) |llvm_name| {
const plus_or_minus = "-+"[@intFromBool(is_enabled)];
try buf.ensureUnusedCapacity(2 + llvm_name.len);
buf.appendAssumeCapacity(plus_or_minus);
buf.appendSliceAssumeCapacity(llvm_name);
buf.appendSliceAssumeCapacity(",");
const is_enabled = target.cpu.features.isEnabled(feature.index);
if (is_enabled) {
try buf.ensureUnusedCapacity(2 + llvm_name.len);
buf.appendAssumeCapacity('+');
buf.appendSliceAssumeCapacity(llvm_name);
buf.appendAssumeCapacity(',');
} else {
try disabled_features.ensureUnusedCapacity(2 + llvm_name.len);
disabled_features.appendAssumeCapacity('-');
disabled_features.appendSliceAssumeCapacity(llvm_name);
disabled_features.appendAssumeCapacity(',');
}
}
}
try buf.appendSlice(disabled_features.items);
if (buf.items.len == 0) break :b "";
assert(std.mem.endsWith(u8, buf.items, ","));
buf.items[buf.items.len - 1] = 0;