make #[target_feature] work with asm register classes

This commit is contained in:
asquared31415 2021-10-07 15:42:18 -04:00
parent d7539a6af0
commit 271da7d8bc
7 changed files with 213 additions and 112 deletions

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@ -202,39 +202,20 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
let mut used_input_regs = FxHashMap::default();
let mut used_output_regs = FxHashMap::default();
let mut required_features: Vec<&str> = vec![];
for (idx, &(ref op, op_sp)) in operands.iter().enumerate() {
if let Some(reg) = op.reg() {
// Make sure we don't accidentally carry features from the
// previous iteration.
required_features.clear();
let reg_class = reg.reg_class();
if reg_class == asm::InlineAsmRegClass::Err {
continue;
}
// We ignore target feature requirements for clobbers: if the
// feature is disabled then the compiler doesn't care what we
// do with the registers.
//
// Note that this is only possible for explicit register
// operands, which cannot be used in the asm string.
let is_clobber = matches!(
op,
hir::InlineAsmOperand::Out {
reg: asm::InlineAsmRegOrRegClass::Reg(_),
late: _,
expr: None
}
);
// Some register classes can only be used as clobbers. This
// means that we disallow passing a value in/out of the asm and
// require that the operand name an explicit register, not a
// register class.
if reg_class.is_clobber_only(asm_arch.unwrap())
&& !(is_clobber && matches!(reg, asm::InlineAsmRegOrRegClass::Reg(_)))
&& !(op.is_clobber() && matches!(reg, asm::InlineAsmRegOrRegClass::Reg(_)))
{
let msg = format!(
"register class `{}` can only be used as a clobber, \
@ -245,47 +226,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
continue;
}
if !is_clobber {
// Validate register classes against currently enabled target
// features. We check that at least one type is available for
// the current target.
for &(_, feature) in reg_class.supported_types(asm_arch.unwrap()) {
if let Some(feature) = feature {
if self.sess.target_features.contains(&Symbol::intern(feature)) {
required_features.clear();
break;
} else {
required_features.push(feature);
}
} else {
required_features.clear();
break;
}
}
// We are sorting primitive strs here and can use unstable sort here
required_features.sort_unstable();
required_features.dedup();
match &required_features[..] {
[] => {}
[feature] => {
let msg = format!(
"register class `{}` requires the `{}` target feature",
reg_class.name(),
feature
);
sess.struct_span_err(op_sp, &msg).emit();
}
features => {
let msg = format!(
"register class `{}` requires at least one target feature: {}",
reg_class.name(),
features.join(", ")
);
sess.struct_span_err(op_sp, &msg).emit();
}
}
}
// Check for conflicts between explicit register operands.
if let asm::InlineAsmRegOrRegClass::Reg(reg) = reg {
let (input, output) = match op {

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@ -2293,6 +2293,13 @@ impl<'hir> InlineAsmOperand<'hir> {
Self::Const { .. } | Self::Sym { .. } => None,
}
}
pub fn is_clobber(&self) -> bool {
matches!(
self,
InlineAsmOperand::Out { reg: InlineAsmRegOrRegClass::Reg(_), late: _, expr: None }
)
}
}
#[derive(Debug, HashStable_Generic)]

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@ -141,6 +141,7 @@ impl ExprVisitor<'tcx> {
template: &[InlineAsmTemplatePiece],
is_input: bool,
tied_input: Option<(&hir::Expr<'tcx>, Option<InlineAsmType>)>,
target_features: &[Symbol],
) -> Option<InlineAsmType> {
// Check the type against the allowed types for inline asm.
let ty = self.typeck_results.expr_ty_adjusted(expr);
@ -283,17 +284,20 @@ impl ExprVisitor<'tcx> {
};
// Check whether the selected type requires a target feature. Note that
// this is different from the feature check we did earlier in AST
// lowering. While AST lowering checked that this register class is
// usable at all with the currently enabled features, some types may
// only be usable with a register class when a certain feature is
// enabled. We check this here since it depends on the results of typeck.
// this is different from the feature check we did earlier. While the
// previous check checked that this register class is usable at all
// with the currently enabled features, some types may only be usable
// with a register class when a certain feature is enabled. We check
// this here since it depends on the results of typeck.
//
// Also note that this check isn't run when the operand type is never
// (!). In that case we still need the earlier check in AST lowering to
// verify that the register class is usable at all.
// (!). In that case we still need the earlier check to verify that the
// register class is usable at all.
if let Some(feature) = feature {
if !self.tcx.sess.target_features.contains(&Symbol::intern(feature)) {
let feat_sym = Symbol::intern(feature);
if !self.tcx.sess.target_features.contains(&feat_sym)
&& !target_features.contains(&feat_sym)
{
let msg = &format!("`{}` target feature is not enabled", feature);
let mut err = self.tcx.sess.struct_span_err(expr.span, msg);
err.note(&format!(
@ -349,23 +353,122 @@ impl ExprVisitor<'tcx> {
Some(asm_ty)
}
fn check_asm(&self, asm: &hir::InlineAsm<'tcx>) {
for (idx, (op, _)) in asm.operands.iter().enumerate() {
fn check_asm(&self, asm: &hir::InlineAsm<'tcx>, hir_id: hir::HirId) {
let hir = self.tcx.hir();
let enclosing_id = hir.enclosing_body_owner(hir_id);
let enclosing_def_id = hir.local_def_id(enclosing_id).to_def_id();
let attrs = self.tcx.codegen_fn_attrs(enclosing_def_id);
for (idx, (op, op_sp)) in asm.operands.iter().enumerate() {
// Validate register classes against currently enabled target
// features. We check that at least one type is available for
// the enabled features.
//
// We ignore target feature requirements for clobbers: if the
// feature is disabled then the compiler doesn't care what we
// do with the registers.
//
// Note that this is only possible for explicit register
// operands, which cannot be used in the asm string.
if let Some(reg) = op.reg() {
if !op.is_clobber() {
let mut missing_required_features = vec![];
let reg_class = reg.reg_class();
for &(_, feature) in reg_class.supported_types(self.tcx.sess.asm_arch.unwrap())
{
match feature {
Some(feature) => {
let feat_sym = Symbol::intern(feature);
if self.tcx.sess.target_features.contains(&feat_sym)
|| attrs.target_features.contains(&feat_sym)
{
missing_required_features.clear();
break;
} else {
missing_required_features.push(feature);
}
}
None => {
missing_required_features.clear();
break;
}
}
}
// We are sorting primitive strs here and can use unstable sort here
missing_required_features.sort_unstable();
missing_required_features.dedup();
match &missing_required_features[..] {
[] => {}
[feature] => {
let msg = format!(
"register class `{}` requires the `{}` target feature",
reg_class.name(),
feature
);
self.tcx.sess.struct_span_err(*op_sp, &msg).emit();
// register isn't enabled, don't do more checks
continue;
}
features => {
let msg = format!(
"register class `{}` requires at least one of the following target features: {}",
reg_class.name(),
features.join(", ")
);
self.tcx.sess.struct_span_err(*op_sp, &msg).emit();
// register isn't enabled, don't do more checks
continue;
}
}
}
}
match *op {
hir::InlineAsmOperand::In { reg, ref expr } => {
self.check_asm_operand_type(idx, reg, expr, asm.template, true, None);
self.check_asm_operand_type(
idx,
reg,
expr,
asm.template,
true,
None,
&attrs.target_features,
);
}
hir::InlineAsmOperand::Out { reg, late: _, ref expr } => {
if let Some(expr) = expr {
self.check_asm_operand_type(idx, reg, expr, asm.template, false, None);
self.check_asm_operand_type(
idx,
reg,
expr,
asm.template,
false,
None,
&attrs.target_features,
);
}
}
hir::InlineAsmOperand::InOut { reg, late: _, ref expr } => {
self.check_asm_operand_type(idx, reg, expr, asm.template, false, None);
self.check_asm_operand_type(
idx,
reg,
expr,
asm.template,
false,
None,
&attrs.target_features,
);
}
hir::InlineAsmOperand::SplitInOut { reg, late: _, ref in_expr, ref out_expr } => {
let in_ty =
self.check_asm_operand_type(idx, reg, in_expr, asm.template, true, None);
let in_ty = self.check_asm_operand_type(
idx,
reg,
in_expr,
asm.template,
true,
None,
&attrs.target_features,
);
if let Some(out_expr) = out_expr {
self.check_asm_operand_type(
idx,
@ -374,6 +477,7 @@ impl ExprVisitor<'tcx> {
asm.template,
false,
Some((in_expr, in_ty)),
&attrs.target_features,
);
}
}
@ -422,7 +526,7 @@ impl Visitor<'tcx> for ExprVisitor<'tcx> {
}
}
hir::ExprKind::InlineAsm(asm) => self.check_asm(asm),
hir::ExprKind::InlineAsm(asm) => self.check_asm(asm, expr.hir_id),
_ => {}
}

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@ -21,10 +21,6 @@ fn main() {
//~^ ERROR asm template modifiers are not allowed for `const` arguments
asm!("{:a}", sym main);
//~^ ERROR asm template modifiers are not allowed for `sym` arguments
asm!("{}", in(zmm_reg) foo);
//~^ ERROR register class `zmm_reg` requires the `avx512f` target feature
asm!("", in("zmm0") foo);
//~^ ERROR register class `zmm_reg` requires the `avx512f` target feature
asm!("", in("ebp") foo);
//~^ ERROR invalid register `ebp`: the frame pointer cannot be used as an operand
asm!("", in("rsp") foo);

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@ -46,86 +46,74 @@ LL | asm!("{:a}", sym main);
| |
| template modifier
error: register class `zmm_reg` requires the `avx512f` target feature
--> $DIR/bad-reg.rs:24:20
|
LL | asm!("{}", in(zmm_reg) foo);
| ^^^^^^^^^^^^^^^
error: register class `zmm_reg` requires the `avx512f` target feature
--> $DIR/bad-reg.rs:26:18
|
LL | asm!("", in("zmm0") foo);
| ^^^^^^^^^^^^^^
error: invalid register `ebp`: the frame pointer cannot be used as an operand for inline asm
--> $DIR/bad-reg.rs:28:18
--> $DIR/bad-reg.rs:24:18
|
LL | asm!("", in("ebp") foo);
| ^^^^^^^^^^^^^
error: invalid register `rsp`: the stack pointer cannot be used as an operand for inline asm
--> $DIR/bad-reg.rs:30:18
--> $DIR/bad-reg.rs:26:18
|
LL | asm!("", in("rsp") foo);
| ^^^^^^^^^^^^^
error: invalid register `ip`: the instruction pointer cannot be used as an operand for inline asm
--> $DIR/bad-reg.rs:32:18
--> $DIR/bad-reg.rs:28:18
|
LL | asm!("", in("ip") foo);
| ^^^^^^^^^^^^
error: invalid register `k0`: the k0 AVX mask register cannot be used as an operand for inline asm
--> $DIR/bad-reg.rs:34:18
--> $DIR/bad-reg.rs:30:18
|
LL | asm!("", in("k0") foo);
| ^^^^^^^^^^^^
error: invalid register `ah`: high byte registers cannot be used as an operand on x86_64
--> $DIR/bad-reg.rs:36:18
--> $DIR/bad-reg.rs:32:18
|
LL | asm!("", in("ah") foo);
| ^^^^^^^^^^^^
error: register class `x87_reg` can only be used as a clobber, not as an input or output
--> $DIR/bad-reg.rs:39:18
--> $DIR/bad-reg.rs:35:18
|
LL | asm!("", in("st(2)") foo);
| ^^^^^^^^^^^^^^^
error: register class `mmx_reg` can only be used as a clobber, not as an input or output
--> $DIR/bad-reg.rs:41:18
--> $DIR/bad-reg.rs:37:18
|
LL | asm!("", in("mm0") foo);
| ^^^^^^^^^^^^^
error: register class `x87_reg` can only be used as a clobber, not as an input or output
--> $DIR/bad-reg.rs:45:20
--> $DIR/bad-reg.rs:41:20
|
LL | asm!("{}", in(x87_reg) foo);
| ^^^^^^^^^^^^^^^
error: register class `mmx_reg` can only be used as a clobber, not as an input or output
--> $DIR/bad-reg.rs:47:20
--> $DIR/bad-reg.rs:43:20
|
LL | asm!("{}", in(mmx_reg) foo);
| ^^^^^^^^^^^^^^^
error: register class `x87_reg` can only be used as a clobber, not as an input or output
--> $DIR/bad-reg.rs:49:20
--> $DIR/bad-reg.rs:45:20
|
LL | asm!("{}", out(x87_reg) _);
| ^^^^^^^^^^^^^^
error: register class `mmx_reg` can only be used as a clobber, not as an input or output
--> $DIR/bad-reg.rs:51:20
--> $DIR/bad-reg.rs:47:20
|
LL | asm!("{}", out(mmx_reg) _);
| ^^^^^^^^^^^^^^
error: register `al` conflicts with register `ax`
--> $DIR/bad-reg.rs:57:33
--> $DIR/bad-reg.rs:53:33
|
LL | asm!("", in("eax") foo, in("al") bar);
| ------------- ^^^^^^^^^^^^ register `al`
@ -133,7 +121,7 @@ LL | asm!("", in("eax") foo, in("al") bar);
| register `ax`
error: register `ax` conflicts with register `ax`
--> $DIR/bad-reg.rs:59:33
--> $DIR/bad-reg.rs:55:33
|
LL | asm!("", in("rax") foo, out("rax") bar);
| ------------- ^^^^^^^^^^^^^^ register `ax`
@ -141,13 +129,13 @@ LL | asm!("", in("rax") foo, out("rax") bar);
| register `ax`
|
help: use `lateout` instead of `out` to avoid conflict
--> $DIR/bad-reg.rs:59:18
--> $DIR/bad-reg.rs:55:18
|
LL | asm!("", in("rax") foo, out("rax") bar);
| ^^^^^^^^^^^^^
error: register `ymm0` conflicts with register `xmm0`
--> $DIR/bad-reg.rs:62:34
--> $DIR/bad-reg.rs:58:34
|
LL | asm!("", in("xmm0") foo, in("ymm0") bar);
| -------------- ^^^^^^^^^^^^^^ register `ymm0`
@ -155,7 +143,7 @@ LL | asm!("", in("xmm0") foo, in("ymm0") bar);
| register `xmm0`
error: register `ymm0` conflicts with register `xmm0`
--> $DIR/bad-reg.rs:64:34
--> $DIR/bad-reg.rs:60:34
|
LL | asm!("", in("xmm0") foo, out("ymm0") bar);
| -------------- ^^^^^^^^^^^^^^^ register `ymm0`
@ -163,10 +151,10 @@ LL | asm!("", in("xmm0") foo, out("ymm0") bar);
| register `xmm0`
|
help: use `lateout` instead of `out` to avoid conflict
--> $DIR/bad-reg.rs:64:18
--> $DIR/bad-reg.rs:60:18
|
LL | asm!("", in("xmm0") foo, out("ymm0") bar);
| ^^^^^^^^^^^^^^
error: aborting due to 23 previous errors
error: aborting due to 21 previous errors

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@ -0,0 +1,40 @@
// only-x86_64
#![feature(asm, avx512_target_feature)]
#[target_feature(enable = "avx")]
unsafe fn foo() {
let mut x = 1;
let y = 2;
asm!("vaddps {2:y}, {0:y}, {1:y}", in(ymm_reg) x, in(ymm_reg) y, lateout(ymm_reg) x);
assert_eq!(x, 3);
}
unsafe fn bar() {
let mut x = 1;
let y = 2;
asm!("vaddps {2:y}, {0:y}, {1:y}", in(ymm_reg) x, in(ymm_reg) y, lateout(ymm_reg) x);
//~^ ERROR: register class `ymm_reg` requires the `avx` target feature
//~| ERROR: register class `ymm_reg` requires the `avx` target feature
//~| ERROR: register class `ymm_reg` requires the `avx` target feature
assert_eq!(x, 3);
}
#[target_feature(enable = "avx512bw")]
unsafe fn baz() {
let x = 1;
asm!("/* {0} */", in(kreg) x);
}
unsafe fn baz2() {
let x = 1;
asm!("/* {0} */", in(kreg) x);
//~^ ERROR: register class `kreg` requires at least one of the following target features: avx512bw, avx512f
}
fn main() {
unsafe {
foo();
bar();
}
}

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@ -0,0 +1,26 @@
error: register class `ymm_reg` requires the `avx` target feature
--> $DIR/target-feature-attr.rs:16:40
|
LL | asm!("vaddps {2:y}, {0:y}, {1:y}", in(ymm_reg) x, in(ymm_reg) y, lateout(ymm_reg) x);
| ^^^^^^^^^^^^^
error: register class `ymm_reg` requires the `avx` target feature
--> $DIR/target-feature-attr.rs:16:55
|
LL | asm!("vaddps {2:y}, {0:y}, {1:y}", in(ymm_reg) x, in(ymm_reg) y, lateout(ymm_reg) x);
| ^^^^^^^^^^^^^
error: register class `ymm_reg` requires the `avx` target feature
--> $DIR/target-feature-attr.rs:16:70
|
LL | asm!("vaddps {2:y}, {0:y}, {1:y}", in(ymm_reg) x, in(ymm_reg) y, lateout(ymm_reg) x);
| ^^^^^^^^^^^^^^^^^^
error: register class `kreg` requires at least one of the following target features: avx512bw, avx512f
--> $DIR/target-feature-attr.rs:31:23
|
LL | asm!("/* {0} */", in(kreg) x);
| ^^^^^^^^^^
error: aborting due to 4 previous errors