bjoernager/rust
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LLVM codgen support for unwinding inline assembly

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This commit is contained in:
cynecx 2021-09-04 19:25:09 +02:00
parent 491dd1f387
commit 91021de1f6
7 changed files with 109 additions and 18 deletions
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29
compiler/rustc_codegen_llvm/src/asm.rs
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@ -1,6 +1,8 @@
use crate::builder::Builder;
use crate::common::Funclet;
use crate::context::CodegenCx;
use crate::llvm;
use crate::llvm_util;
use crate::type_::Type;
use crate::type_of::LayoutLlvmExt;
use crate::value::Value;
@ -98,6 +100,8 @@ impl AsmBuilderMethods<'tcx> for Builder<'a, 'll, 'tcx> {
ia.alignstack,
ia.dialect,
&[span],
false,
None,
);
if r.is_none() {
return false;
@ -121,6 +125,7 @@ impl AsmBuilderMethods<'tcx> for Builder<'a, 'll, 'tcx> {
options: InlineAsmOptions,
line_spans: &[Span],
instance: Instance<'_>,
dest_catch_funclet: Option<(Self::BasicBlock, Self::BasicBlock, Option<&Self::Funclet>)>,
) {
let asm_arch = self.tcx.sess.asm_arch.unwrap();
@ -355,6 +360,8 @@ impl AsmBuilderMethods<'tcx> for Builder<'a, 'll, 'tcx> {
alignstack,
dialect,
line_spans,
options.contains(InlineAsmOptions::MAY_UNWIND),
dest_catch_funclet,
)
.unwrap_or_else(|| span_bug!(line_spans[0], "LLVM asm constraint validation failed"));
@ -447,10 +454,16 @@ pub(crate) fn inline_asm_call(
alignstack: bool,
dia: LlvmAsmDialect,
line_spans: &[Span],
unwind: bool,
dest_catch_funclet: Option<(
&'ll llvm::BasicBlock,
&'ll llvm::BasicBlock,
Option<&Funclet<'ll>>,
)>,
) -> Option<&'ll Value> {
let volatile = if volatile { llvm::True } else { llvm::False };
let alignstack = if alignstack { llvm::True } else { llvm::False };
let can_throw = llvm::False;
let can_throw = if unwind { llvm::True } else { llvm::False };
let argtys = inputs
.iter()
@ -467,6 +480,13 @@ pub(crate) fn inline_asm_call(
let constraints_ok = llvm::LLVMRustInlineAsmVerify(fty, cons.as_ptr().cast(), cons.len());
debug!("constraint verification result: {:?}", constraints_ok);
if constraints_ok {
if unwind && llvm_util::get_version() < (13, 0, 0) {
bx.cx.sess().span_fatal(
line_spans[0],
"unwinding from inline assembly is only supported on llvm >= 13.",
);
}
let v = llvm::LLVMRustInlineAsm(
fty,
asm.as_ptr().cast(),
@ -478,7 +498,12 @@ pub(crate) fn inline_asm_call(
llvm::AsmDialect::from_generic(dia),
can_throw,
);
let call = bx.call(fty, v, inputs, None);
let call = if let Some((dest, catch, funclet)) = dest_catch_funclet {
bx.invoke(fty, v, inputs, dest, catch, funclet)
} else {
bx.call(fty, v, inputs, None)
};
// Store mark in a metadata node so we can map LLVM errors
// back to source locations. See #17552.