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| author | Richard Henderson <richard.henderson@linaro.org> | 2025-09-18 07:05:58 -0700 |
|---|---|---|
| committer | Richard Henderson <richard.henderson@linaro.org> | 2025-09-18 07:05:59 -0700 |
| commit | ccafa85a97e38698b798115bba6c18c849846e25 (patch) | |
| tree | a7d4941f050d4b621cffe2a71657a1bd39c35d4b /rust/qemu-macros/src/bits.rs | |
| parent | f0007b7f03e2d7fc33e71c3a582f2364c51a226b (diff) | |
| parent | 00c0911c68e5bd664de1a261b74c390f4c0be83d (diff) | |
| download | focaccia-qemu-ccafa85a97e38698b798115bba6c18c849846e25.tar.gz focaccia-qemu-ccafa85a97e38698b798115bba6c18c849846e25.zip | |
Merge tag 'for-upstream' of https://gitlab.com/bonzini/qemu into staging
* cpu-exec: more cleanups to CPU loop exits * python: bump bundled Meson to 1.9.0 * rust: require Rust 1.83.0 * rust: temporarily remove from Ubuntu CI * rust: vmstate: convert to use builder pattern * rust: split "qemu-api" crate * rust: rename qemu_api_macros -> qemu_macros * rust: re-export qemu macros from other crates * x86: fix functional test failure for Xen emulation * x86: cleanups # -----BEGIN PGP SIGNATURE----- # # iQFIBAABCgAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmjK6ZsUHHBib256aW5p # QHJlZGhhdC5jb20ACgkQv/vSX3jHroNBKwf/aadInCT4vASOfpxbwZgYfYgR2m2m # BJE9oYKxZJ6MlEOU/1Wfywf9fg4leMSh3XxkDKkEIL19yS6emwin8n3SNYrdAFn3 # 6u4IIWO4NI1Ht3NKytrqFk9wtbH9pAs/gVHLlnmpMxIqtOtZLumPAKNz8rlantmK # UVDYL3Y0L4pD9i5FK1ObMNpk5AsWNr8Tr64fmb+nTkHutld3sBrEMCLI0+EByGyN # lQ16sLn9PGqHOr210zuQP7wP2T3NCI3YokFSPQrUUL8LZGxRdXoNF4hI4uZDKGdn # UbtRu9EkM052qzfsFMrEw5JSbdxEfIjKlPoFKseMv+aWvNAuximAraD3Vg== # =Lr+x # -----END PGP SIGNATURE----- # gpg: Signature made Wed 17 Sep 2025 10:02:19 AM PDT # gpg: using RSA key F13338574B662389866C7682BFFBD25F78C7AE83 # gpg: issuer "pbonzini@redhat.com" # gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" [unknown] # gpg: aka "Paolo Bonzini <pbonzini@redhat.com>" [unknown] # gpg: WARNING: The key's User ID is not certified with a trusted signature! # gpg: There is no indication that the signature belongs to the owner. # Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4 E2F7 7E15 100C CD36 69B1 # Subkey fingerprint: F133 3857 4B66 2389 866C 7682 BFFB D25F 78C7 AE83 * tag 'for-upstream' of https://gitlab.com/bonzini/qemu: (60 commits) accel/kvm: Set guest_memfd_offset to non-zero value only when guest_memfd is valid accel/kvm: Zero out mem explicitly in kvm_set_user_memory_region() accel/kvm: Switch to check KVM_CAP_GUEST_MEMFD and KVM_CAP_USER_MEMORY2 on VM i386/kvm: Drop KVM_CAP_X86_SMM check in kvm_arch_init() multiboot: Fix the split lock target/i386: Define enum X86ASIdx for x86's address spaces i386/cpu: Enable SMM cpu address space under KVM hpet: guard IRQ handling with BQL rust: do not inline do_init_io rust: meson: remove unnecessary complication in device crates docs: update rust.rst rust: re-export qemu macros from common/qom/hwcore rust: re-export qemu_macros internal helper in "bits" rust: repurpose qemu_api -> tests rust/pl011: drop dependency on qemu_api rust/hpet: drop now unneeded qemu_api dep rust: rename qemu_api_macros -> qemu_macros rust: split "hwcore" crate rust: split "system" crate rust: split "chardev" crate ... Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Diffstat (limited to 'rust/qemu-macros/src/bits.rs')
| -rw-r--r-- | rust/qemu-macros/src/bits.rs | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/rust/qemu-macros/src/bits.rs b/rust/qemu-macros/src/bits.rs new file mode 100644 index 0000000000..a80a3b9fee --- /dev/null +++ b/rust/qemu-macros/src/bits.rs @@ -0,0 +1,213 @@ +// SPDX-License-Identifier: MIT or Apache-2.0 or GPL-2.0-or-later + +// shadowing is useful together with "if let" +#![allow(clippy::shadow_unrelated)] + +use proc_macro2::{ + Delimiter, Group, Ident, Punct, Spacing, Span, TokenStream, TokenTree, TokenTree as TT, +}; +use syn::Error; + +pub struct BitsConstInternal { + typ: TokenTree, +} + +fn paren(ts: TokenStream) -> TokenTree { + TT::Group(Group::new(Delimiter::Parenthesis, ts)) +} + +fn ident(s: &'static str) -> TokenTree { + TT::Ident(Ident::new(s, Span::call_site())) +} + +fn punct(ch: char) -> TokenTree { + TT::Punct(Punct::new(ch, Spacing::Alone)) +} + +/// Implements a recursive-descent parser that translates Boolean expressions on +/// bitmasks to invocations of `const` functions defined by the `bits!` macro. +impl BitsConstInternal { + // primary ::= '(' or ')' + // | ident + // | '!' ident + fn parse_primary( + &self, + tok: TokenTree, + it: &mut dyn Iterator<Item = TokenTree>, + out: &mut TokenStream, + ) -> Result<Option<TokenTree>, Error> { + let next = match tok { + TT::Group(ref g) => { + if g.delimiter() != Delimiter::Parenthesis && g.delimiter() != Delimiter::None { + return Err(Error::new(g.span(), "expected parenthesis")); + } + let mut stream = g.stream().into_iter(); + let Some(first_tok) = stream.next() else { + return Err(Error::new(g.span(), "expected operand, found ')'")); + }; + let mut output = TokenStream::new(); + // start from the lowest precedence + let next = self.parse_or(first_tok, &mut stream, &mut output)?; + if let Some(tok) = next { + return Err(Error::new(tok.span(), format!("unexpected token {tok}"))); + } + out.extend(Some(paren(output))); + it.next() + } + TT::Ident(_) => { + let mut output = TokenStream::new(); + output.extend([ + self.typ.clone(), + TT::Punct(Punct::new(':', Spacing::Joint)), + TT::Punct(Punct::new(':', Spacing::Joint)), + tok, + ]); + out.extend(Some(paren(output))); + it.next() + } + TT::Punct(ref p) => { + if p.as_char() != '!' { + return Err(Error::new(p.span(), "expected operand")); + } + let Some(rhs_tok) = it.next() else { + return Err(Error::new(p.span(), "expected operand at end of input")); + }; + let next = self.parse_primary(rhs_tok, it, out)?; + out.extend([punct('.'), ident("invert"), paren(TokenStream::new())]); + next + } + _ => { + return Err(Error::new(tok.span(), "unexpected literal")); + } + }; + Ok(next) + } + + fn parse_binop< + F: Fn( + &Self, + TokenTree, + &mut dyn Iterator<Item = TokenTree>, + &mut TokenStream, + ) -> Result<Option<TokenTree>, Error>, + >( + &self, + tok: TokenTree, + it: &mut dyn Iterator<Item = TokenTree>, + out: &mut TokenStream, + ch: char, + f: F, + method: &'static str, + ) -> Result<Option<TokenTree>, Error> { + let mut next = f(self, tok, it, out)?; + while next.is_some() { + let op = next.as_ref().unwrap(); + let TT::Punct(ref p) = op else { break }; + if p.as_char() != ch { + break; + } + + let Some(rhs_tok) = it.next() else { + return Err(Error::new(p.span(), "expected operand at end of input")); + }; + let mut rhs = TokenStream::new(); + next = f(self, rhs_tok, it, &mut rhs)?; + out.extend([punct('.'), ident(method), paren(rhs)]); + } + Ok(next) + } + + // sub ::= primary ('-' primary)* + pub fn parse_sub( + &self, + tok: TokenTree, + it: &mut dyn Iterator<Item = TokenTree>, + out: &mut TokenStream, + ) -> Result<Option<TokenTree>, Error> { + self.parse_binop(tok, it, out, '-', Self::parse_primary, "difference") + } + + // and ::= sub ('&' sub)* + fn parse_and( + &self, + tok: TokenTree, + it: &mut dyn Iterator<Item = TokenTree>, + out: &mut TokenStream, + ) -> Result<Option<TokenTree>, Error> { + self.parse_binop(tok, it, out, '&', Self::parse_sub, "intersection") + } + + // xor ::= and ('&' and)* + fn parse_xor( + &self, + tok: TokenTree, + it: &mut dyn Iterator<Item = TokenTree>, + out: &mut TokenStream, + ) -> Result<Option<TokenTree>, Error> { + self.parse_binop(tok, it, out, '^', Self::parse_and, "symmetric_difference") + } + + // or ::= xor ('|' xor)* + pub fn parse_or( + &self, + tok: TokenTree, + it: &mut dyn Iterator<Item = TokenTree>, + out: &mut TokenStream, + ) -> Result<Option<TokenTree>, Error> { + self.parse_binop(tok, it, out, '|', Self::parse_xor, "union") + } + + pub fn parse( + it: &mut dyn Iterator<Item = TokenTree>, + ) -> Result<proc_macro2::TokenStream, Error> { + let mut pos = Span::call_site(); + let mut typ = proc_macro2::TokenStream::new(); + + // Gobble everything up to an `@` sign, which is followed by a + // parenthesized expression; that is, all token trees except the + // last two form the type. + let next = loop { + let tok = it.next(); + if let Some(ref t) = tok { + pos = t.span(); + } + match tok { + None => break None, + Some(TT::Punct(ref p)) if p.as_char() == '@' => { + let tok = it.next(); + if let Some(ref t) = tok { + pos = t.span(); + } + break tok; + } + Some(x) => typ.extend(Some(x)), + } + }; + + let Some(tok) = next else { + return Err(Error::new( + pos, + "expected expression, do not call this macro directly", + )); + }; + let TT::Group(ref _group) = tok else { + return Err(Error::new( + tok.span(), + "expected parenthesis, do not call this macro directly", + )); + }; + let mut out = TokenStream::new(); + let state = Self { + typ: TT::Group(Group::new(Delimiter::None, typ)), + }; + + let next = state.parse_primary(tok, it, &mut out)?; + + // A parenthesized expression is a single production of the grammar, + // so the input must have reached the last token. + if let Some(tok) = next { + return Err(Error::new(tok.span(), format!("unexpected token {tok}"))); + } + Ok(out) + } +} |