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| author | Jacob Young <jacobly0@users.noreply.github.com> | 2025-07-25 16:38:17 -0400 |
|---|---|---|
| committer | Jacob Young <jacobly0@users.noreply.github.com> | 2025-07-26 16:08:40 -0400 |
| commit | 1274254c48ee105623c513dfc01451fee2912c5b (patch) | |
| tree | 612ff85297941fe4f7108ec62fd9ec28038d59a8 /src/codegen | |
| parent | 7c349da49c73817139444570d3082ac1f0c93078 (diff) | |
| download | zig-1274254c48ee105623c513dfc01451fee2912c5b.tar.gz zig-1274254c48ee105623c513dfc01451fee2912c5b.zip | |
aarch64: implement stack probing
Diffstat (limited to 'src/codegen')
| -rw-r--r-- | src/codegen/aarch64/Select.zig | 73 | ||||
| -rw-r--r-- | src/codegen/aarch64/encoding.zig | 2 |
2 files changed, 51 insertions, 24 deletions
diff --git a/src/codegen/aarch64/Select.zig b/src/codegen/aarch64/Select.zig index 0a50cb6c9d..b0b1297a93 100644 --- a/src/codegen/aarch64/Select.zig +++ b/src/codegen/aarch64/Select.zig @@ -6693,8 +6693,8 @@ pub fn layout( wip_mir_log.debug("{f}<body>:\n", .{nav.fqn.fmt(ip)}); const stack_size: u24 = @intCast(InternPool.Alignment.@"16".forward(isel.stack_size)); - const stack_size_low: u12 = @truncate(stack_size >> 0); - const stack_size_high: u12 = @truncate(stack_size >> 12); + const stack_size_lo: u12 = @truncate(stack_size >> 0); + const stack_size_hi: u12 = @truncate(stack_size >> 12); var saves_buf: [10 + 8 + 8 + 2 + 8]struct { class: enum { integer, vector }, @@ -6881,28 +6881,53 @@ pub fn layout( } } + try isel.emit(.add(.fp, .sp, .{ .immediate = frame_record_offset })); const scratch_reg: Register = if (isel.stack_align == .@"16") .sp - else if (stack_size == 0) + else if (stack_size == 0 and frame_record_offset == 0) .fp else - .x9; - try isel.emit(.add(.fp, .sp, .{ .immediate = frame_record_offset })); - if (stack_size_high > 0) try isel.emit(.sub(scratch_reg, .sp, .{ - .shifted_immediate = .{ .immediate = stack_size_high, .lsl = .@"12" }, - })); - if (stack_size_low > 0) try isel.emit(.sub( - scratch_reg, - if (stack_size_high > 0) scratch_reg else .sp, - .{ .immediate = stack_size_low }, - )); - if (isel.stack_align != .@"16") { - try isel.emit(.@"and"(.sp, scratch_reg, .{ .immediate = .{ - .N = .doubleword, - .immr = -%isel.stack_align.toLog2Units(), - .imms = ~isel.stack_align.toLog2Units(), - } })); + .ip0; + if (mod.stack_check) { + if (stack_size_hi > 2) { + try isel.movImmediate(.ip1, stack_size_hi); + const loop_label = isel.instructions.items.len; + try isel.emit(.sub(.sp, .sp, .{ + .shifted_immediate = .{ .immediate = 1, .lsl = .@"12" }, + })); + try isel.emit(.sub(.ip1, .ip1, .{ .immediate = 1 })); + try isel.emit(.ldr(.xzr, .{ .base = .sp })); + try isel.emit(.cbnz(.ip1, -@as(i21, @intCast( + (isel.instructions.items.len - loop_label) << 2, + )))); + } else for (0..stack_size_hi) |_| { + try isel.emit(.sub(.sp, .sp, .{ + .shifted_immediate = .{ .immediate = 1, .lsl = .@"12" }, + })); + try isel.emit(.ldr(.xzr, .{ .base = .sp })); + } + if (stack_size_lo > 0) try isel.emit(.sub( + scratch_reg, + .sp, + .{ .immediate = stack_size_lo }, + )) else if (scratch_reg.alias == Register.Alias.ip0) + try isel.emit(.add(scratch_reg, .sp, .{ .immediate = 0 })); + } else { + if (stack_size_hi > 0) try isel.emit(.sub(scratch_reg, .sp, .{ + .shifted_immediate = .{ .immediate = stack_size_hi, .lsl = .@"12" }, + })); + if (stack_size_lo > 0) try isel.emit(.sub( + scratch_reg, + if (stack_size_hi > 0) scratch_reg else .sp, + .{ .immediate = stack_size_lo }, + )) else if (scratch_reg.alias == Register.Alias.ip0 and stack_size_hi == 0) + try isel.emit(.add(scratch_reg, .sp, .{ .immediate = 0 })); } + if (isel.stack_align != .@"16") try isel.emit(.@"and"(.sp, scratch_reg, .{ .immediate = .{ + .N = .doubleword, + .immr = -%isel.stack_align.toLog2Units(), + .imms = ~isel.stack_align.toLog2Units(), + } })); wip_mir_log.debug("", .{}); } @@ -6947,17 +6972,17 @@ pub fn layout( save_index += 1; } else save_index += 1; } - if (isel.stack_align != .@"16" or (stack_size_low > 0 and stack_size_high > 0)) { + if (isel.stack_align != .@"16" or (stack_size_lo > 0 and stack_size_hi > 0)) { try isel.emit(switch (frame_record_offset) { 0 => .add(.sp, .fp, .{ .immediate = 0 }), else => |offset| .sub(.sp, .fp, .{ .immediate = offset }), }); } else { - if (stack_size_high > 0) try isel.emit(.add(.sp, .sp, .{ - .shifted_immediate = .{ .immediate = stack_size_high, .lsl = .@"12" }, + if (stack_size_hi > 0) try isel.emit(.add(.sp, .sp, .{ + .shifted_immediate = .{ .immediate = stack_size_hi, .lsl = .@"12" }, })); - if (stack_size_low > 0) try isel.emit(.add(.sp, .sp, .{ - .immediate = stack_size_low, + if (stack_size_lo > 0) try isel.emit(.add(.sp, .sp, .{ + .immediate = stack_size_lo, })); } wip_mir_log.debug("{f}<epilogue>:\n", .{nav.fqn.fmt(ip)}); diff --git a/src/codegen/aarch64/encoding.zig b/src/codegen/aarch64/encoding.zig index 1697b2957b..727b88c729 100644 --- a/src/codegen/aarch64/encoding.zig +++ b/src/codegen/aarch64/encoding.zig @@ -151,6 +151,7 @@ pub const Register = struct { pub const wzr: Register = .{ .alias = .zr, .format = .{ .integer = .word } }; pub const wsp: Register = .{ .alias = .sp, .format = .{ .integer = .word } }; + pub const ip = x16; pub const ip0 = x16; pub const ip1 = x17; pub const fp = x29; @@ -774,6 +775,7 @@ pub const Register = struct { ffr, + pub const ip: Alias = .r16; pub const ip0: Alias = .r16; pub const ip1: Alias = .r17; pub const fp: Alias = .r29; |