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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 12:03:36 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 12:03:36 +0000 |
commit | 17d40c6057c88f4c432b0d7bac88e1b84cb7e67f (patch) | |
tree | 3f66c4a5918660bb8a758ab6cda5ff8ee4f6cdcd /compiler/rustc_target/src/abi/call/aarch64.rs | |
parent | Adding upstream version 1.64.0+dfsg1. (diff) | |
download | rustc-f7f0cc2a5d72e2c61c1f6900e70eec992bea4273.tar.xz rustc-f7f0cc2a5d72e2c61c1f6900e70eec992bea4273.zip |
Adding upstream version 1.65.0+dfsg1.upstream/1.65.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | compiler/rustc_target/src/abi/call/aarch64.rs | 43 |
1 files changed, 35 insertions, 8 deletions
diff --git a/compiler/rustc_target/src/abi/call/aarch64.rs b/compiler/rustc_target/src/abi/call/aarch64.rs index 4613a459c..a84988fa7 100644 --- a/compiler/rustc_target/src/abi/call/aarch64.rs +++ b/compiler/rustc_target/src/abi/call/aarch64.rs @@ -1,6 +1,27 @@ use crate::abi::call::{ArgAbi, FnAbi, Reg, RegKind, Uniform}; use crate::abi::{HasDataLayout, TyAbiInterface}; +/// Given integer-types M and register width N (e.g. M=u16 and N=32 bits), the +/// `ParamExtension` policy specifies how a uM value should be treated when +/// passed via register or stack-slot of width N. See also rust-lang/rust#97463. +#[derive(Copy, Clone, PartialEq)] +pub enum ParamExtension { + /// Indicates that when passing an i8/i16, either as a function argument or + /// as a return value, it must be sign-extended to 32 bits, and likewise a + /// u8/u16 must be zero-extended to 32-bits. (This variant is here to + /// accommodate Apple's deviation from the usual AArch64 ABI as defined by + /// ARM.) + /// + /// See also: <https://developer.apple.com/documentation/xcode/writing-arm64-code-for-apple-platforms#Pass-Arguments-to-Functions-Correctly> + ExtendTo32Bits, + + /// Indicates that no sign- nor zero-extension is performed: if a value of + /// type with bitwidth M is passed as function argument or return value, + /// then M bits are copied into the least significant M bits, and the + /// remaining bits of the register (or word of memory) are untouched. + NoExtension, +} + fn is_homogeneous_aggregate<'a, Ty, C>(cx: &C, arg: &mut ArgAbi<'a, Ty>) -> Option<Uniform> where Ty: TyAbiInterface<'a, C> + Copy, @@ -24,13 +45,16 @@ where }) } -fn classify_ret<'a, Ty, C>(cx: &C, ret: &mut ArgAbi<'a, Ty>) +fn classify_ret<'a, Ty, C>(cx: &C, ret: &mut ArgAbi<'a, Ty>, param_policy: ParamExtension) where Ty: TyAbiInterface<'a, C> + Copy, C: HasDataLayout, { if !ret.layout.is_aggregate() { - ret.extend_integer_width_to(32); + match param_policy { + ParamExtension::ExtendTo32Bits => ret.extend_integer_width_to(32), + ParamExtension::NoExtension => {} + } return; } if let Some(uniform) = is_homogeneous_aggregate(cx, ret) { @@ -46,13 +70,16 @@ where ret.make_indirect(); } -fn classify_arg<'a, Ty, C>(cx: &C, arg: &mut ArgAbi<'a, Ty>) +fn classify_arg<'a, Ty, C>(cx: &C, arg: &mut ArgAbi<'a, Ty>, param_policy: ParamExtension) where Ty: TyAbiInterface<'a, C> + Copy, C: HasDataLayout, { if !arg.layout.is_aggregate() { - arg.extend_integer_width_to(32); + match param_policy { + ParamExtension::ExtendTo32Bits => arg.extend_integer_width_to(32), + ParamExtension::NoExtension => {} + } return; } if let Some(uniform) = is_homogeneous_aggregate(cx, arg) { @@ -68,19 +95,19 @@ where arg.make_indirect(); } -pub fn compute_abi_info<'a, Ty, C>(cx: &C, fn_abi: &mut FnAbi<'a, Ty>) +pub fn compute_abi_info<'a, Ty, C>(cx: &C, fn_abi: &mut FnAbi<'a, Ty>, param_policy: ParamExtension) where Ty: TyAbiInterface<'a, C> + Copy, C: HasDataLayout, { if !fn_abi.ret.is_ignore() { - classify_ret(cx, &mut fn_abi.ret); + classify_ret(cx, &mut fn_abi.ret, param_policy); } - for arg in &mut fn_abi.args { + for arg in fn_abi.args.iter_mut() { if arg.is_ignore() { continue; } - classify_arg(cx, arg); + classify_arg(cx, arg, param_policy); } } |