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stage2 aarch64: add basic function pro/epilogue

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Fix typo in `nop` implementation.
Simplify `aarch64` macOS tests.
This commit is contained in:
Jakub Konka
2021-01-17 11:26:02 +01:00
parent e292f33de7
commit b25cf7db02
3 changed files with 88 additions and 81 deletions
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66
src/codegen.zig
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@@ -637,6 +637,67 @@ fn Function(comptime arch: std.Target.Cpu.Arch) type {
try self.dbgSetEpilogueBegin();
}
},
.aarch64, .aarch64_be, .aarch64_32 => {
const cc = self.fn_type.fnCallingConvention();
if (cc != .Naked) {
// TODO Finish function prologue and epilogue for aarch64.
// Reserve the stack for local variables, etc.
// stp fp, lr, [sp, #-16]!
writeInt(u32, try self.code.addManyAsArray(4), Instruction.stp(
.x29,
.x30,
Register.sp,
Instruction.LoadStorePairOffset.pre_index(-16),
).toU32());
try self.dbgSetPrologueEnd();
try self.genBody(self.mod_fn.body);
try self.dbgSetEpilogueBegin();
// exitlude jumps
if (self.exitlude_jump_relocs.items.len == 1) {
// There is only one relocation. Hence,
// this relocation must be at the end of
// the code. Therefore, we can just delete
// the space initially reserved for the
// jump
self.code.items.len -= 4;
} else for (self.exitlude_jump_relocs.items) |jmp_reloc| {
const amt = @intCast(i32, self.code.items.len) - @intCast(i32, jmp_reloc + 8);
if (amt == -4) {
// This return is at the end of the
// code block. We can't just delete
// the space because there may be
// other jumps we already relocated to
// the address. Instead, insert a nop
writeInt(u32, self.code.items[jmp_reloc..][0..4], Instruction.nop().toU32());
} else {
if (math.cast(i28, amt)) |offset| {
writeInt(u32, self.code.items[jmp_reloc..][0..4], Instruction.b(offset).toU32());
} else |err| {
return self.failSymbol("exitlude jump is too large", .{});
}
}
}
// ldp fp, lr, [sp], #16
writeInt(u32, try self.code.addManyAsArray(4), Instruction.ldp(
.x29,
.x30,
Register.sp,
Instruction.LoadStorePairOffset.post_index(16),
).toU32());
// ret lr
writeInt(u32, try self.code.addManyAsArray(4), Instruction.ret(null).toU32());
} else {
try self.dbgSetPrologueEnd();
try self.genBody(self.mod_fn.body);
try self.dbgSetEpilogueBegin();
}
},
else => {
try self.dbgSetPrologueEnd();
try self.genBody(self.mod_fn.body);
@@ -1962,8 +2023,9 @@ fn Function(comptime arch: std.Target.Cpu.Arch) type {
try self.exitlude_jump_relocs.append(self.gpa, self.code.items.len - 4);
},
.aarch64 => {
// TODO: relocations
writeInt(u32, try self.code.addManyAsArray(4), Instruction.ret(null).toU32());
// Just add space for an instruction, patch this later
try self.code.resize(self.code.items.len + 4);
try self.exitlude_jump_relocs.append(self.gpa, self.code.items.len - 4);
},
else => return self.fail(src, "TODO implement return for {}", .{self.target.cpu.arch}),
}