| author |  Alex Rønne Petersen <alex@alexrp.com> 2024-10-15 21:28:42+02:00 |
| committer | Alex Rønne Petersen <alex@alexrp.com> 2024-10-20 09:21:17+02:00 |
| log | ef72b91ac2b96ba64a53b08a661e9ad83a828ee4 |
| tree | 03d0c78049441a867629d0534a98face6703e578 |
| parent | d2f04e919c833288d5cf1efa97c25bbaae101168 |
| signature |  Signed by SSH key SHA256:7B/LJ7bpR1eX8aCXSr4mtd5M45VMPKcx9zY8e95b5QM |
compiler: Remove uses of defaultFunctionAlignment() in the frontend.
minFunctionAlignment() is something we can know ahead of time for any given
target because it's a matter of ABI. However, defaultFunctionAlignment() is a
matter of optimization and every backend can do it differently depending on any
number of factors. For example, LLVM will base the choice on the CPU model in
its aarch64 backend. So just don't use this value in the frontend.3 files changed, 5 insertions(+), 8 deletions(-)
src/Sema.zig+2-6
| ... | @@ -26572,9 +26572,7 @@ fn zirFuncFancy(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!A | ... | @@ -26572,9 +26572,7 @@ fn zirFuncFancy(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!A |
| 26572 | if (val.isGenericPoison()) { | 26572 | if (val.isGenericPoison()) { |
| 26573 | break :blk null; | 26573 | break :blk null; |
| 26574 | } | 26574 | } |
| 26575 | const alignment = try sema.validateAlignAllowZero(block, align_src, try val.toUnsignedIntSema(pt)); | 26575 | break :blk try sema.validateAlignAllowZero(block, align_src, try val.toUnsignedIntSema(pt)); |
| 26576 | const default = target_util.defaultFunctionAlignment(target); | ||
| 26577 | break :blk if (alignment == default) .none else alignment; | ||
| 26578 | } else if (extra.data.bits.has_align_ref) blk: { | 26576 | } else if (extra.data.bits.has_align_ref) blk: { |
| 26579 | const align_ref: Zir.Inst.Ref = @enumFromInt(sema.code.extra[extra_index]); | 26577 | const align_ref: Zir.Inst.Ref = @enumFromInt(sema.code.extra[extra_index]); |
| 26580 | extra_index += 1; | 26578 | extra_index += 1; |
| ... | @@ -26592,9 +26590,7 @@ fn zirFuncFancy(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!A | ... | @@ -26592,9 +26590,7 @@ fn zirFuncFancy(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!A |
| 26592 | error.GenericPoison => break :blk null, | 26590 | error.GenericPoison => break :blk null, |
| 26593 | else => |e| return e, | 26591 | else => |e| return e, |
| 26594 | }; | 26592 | }; |
| 26595 | const alignment = try sema.validateAlignAllowZero(block, align_src, try align_val.toUnsignedIntSema(pt)); | 26593 | break :blk try sema.validateAlignAllowZero(block, align_src, try align_val.toUnsignedIntSema(pt)); |
| 26596 | const default = target_util.defaultFunctionAlignment(target); | ||
| 26597 | break :blk if (alignment == default) .none else alignment; | ||
| 26598 | } else .none; | 26594 | } else .none; |
| 26599 | 26595 | ||
| 26600 | const @"addrspace": ?std.builtin.AddressSpace = if (extra.data.bits.has_addrspace_body) blk: { | 26596 | const @"addrspace": ?std.builtin.AddressSpace = if (extra.data.bits.has_addrspace_body) blk: { |
src/Type.zig+1-1
| ... | @@ -1020,7 +1020,7 @@ pub fn abiAlignmentInner( | ... | @@ -1020,7 +1020,7 @@ pub fn abiAlignmentInner( |
| 1020 | }, | 1020 | }, |
| 1021 | 1021 | ||
| 1022 | // represents machine code; not a pointer | 1022 | // represents machine code; not a pointer |
| 1023 | .func_type => return .{ .scalar = target_util.defaultFunctionAlignment(target) }, | 1023 | .func_type => return .{ .scalar = target_util.minFunctionAlignment(target) }, |
| 1024 | 1024 | ||
| 1025 | .simple_type => |t| switch (t) { | 1025 | .simple_type => |t| switch (t) { |
| 1026 | .bool, | 1026 | .bool, |
src/target.zig+2-1
| ... | @@ -459,7 +459,8 @@ pub fn llvmMachineAbi(target: std.Target) ?[:0]const u8 { | ... | @@ -459,7 +459,8 @@ pub fn llvmMachineAbi(target: std.Target) ?[:0]const u8 { |
| 459 | } | 459 | } |
| 460 | } | 460 | } |
| 461 | 461 | ||
| 462 | /// This function returns 1 if function alignment is not observable or settable. | 462 | /// This function returns 1 if function alignment is not observable or settable. Note that this |
| 463 | /// value will not necessarily match the backend's default function alignment (e.g. for LLVM). | ||
| 463 | pub fn defaultFunctionAlignment(target: std.Target) Alignment { | 464 | pub fn defaultFunctionAlignment(target: std.Target) Alignment { |
| 464 | // Overrides of the minimum for performance. | 465 | // Overrides of the minimum for performance. |
| 465 | return switch (target.cpu.arch) { | 466 | return switch (target.cpu.arch) { |