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Diffstat (limited to 'tests/codegen/intrinsics/transmute.rs')
| -rw-r--r-- | tests/codegen/intrinsics/transmute.rs | 431 |
1 files changed, 431 insertions, 0 deletions
diff --git a/tests/codegen/intrinsics/transmute.rs b/tests/codegen/intrinsics/transmute.rs new file mode 100644 index 000000000..57f901c67 --- /dev/null +++ b/tests/codegen/intrinsics/transmute.rs @@ -0,0 +1,431 @@ +// compile-flags: -O -C no-prepopulate-passes +// only-64bit (so I don't need to worry about usize) +// min-llvm-version: 15.0 # this test assumes `ptr`s + +#![crate_type = "lib"] +#![feature(core_intrinsics)] +#![feature(custom_mir)] +#![feature(inline_const)] +#![allow(unreachable_code)] + +use std::mem::{transmute, MaybeUninit}; + +// Some of the cases here are statically rejected by `mem::transmute`, so +// we need to generate custom MIR for those cases to get to codegen. +use std::intrinsics::mir::*; + +enum Never {} + +#[repr(align(2))] +pub struct BigNever(Never, u16, Never); + +#[repr(align(8))] +pub struct Scalar64(i64); + +#[repr(C, align(4))] +pub struct Aggregate64(u16, u8, i8, f32); + +#[repr(C)] +pub struct Aggregate8(u8); + +// CHECK-LABEL: @check_bigger_size( +#[no_mangle] +#[custom_mir(dialect = "runtime", phase = "initial")] +pub unsafe fn check_bigger_size(x: u16) -> u32 { + // CHECK: call void @llvm.trap + mir!{ + { + RET = CastTransmute(x); + Return() + } + } +} + +// CHECK-LABEL: @check_smaller_size( +#[no_mangle] +#[custom_mir(dialect = "runtime", phase = "initial")] +pub unsafe fn check_smaller_size(x: u32) -> u16 { + // CHECK: call void @llvm.trap + mir!{ + { + RET = CastTransmute(x); + Return() + } + } +} + +// CHECK-LABEL: @check_smaller_array( +#[no_mangle] +#[custom_mir(dialect = "runtime", phase = "initial")] +pub unsafe fn check_smaller_array(x: [u32; 7]) -> [u32; 3] { + // CHECK: call void @llvm.trap + mir!{ + { + RET = CastTransmute(x); + Return() + } + } +} + +// CHECK-LABEL: @check_bigger_array( +#[no_mangle] +#[custom_mir(dialect = "runtime", phase = "initial")] +pub unsafe fn check_bigger_array(x: [u32; 3]) -> [u32; 7] { + // CHECK: call void @llvm.trap + mir!{ + { + RET = CastTransmute(x); + Return() + } + } +} + +// CHECK-LABEL: @check_to_uninhabited( +#[no_mangle] +#[custom_mir(dialect = "runtime", phase = "initial")] +pub unsafe fn check_to_uninhabited(x: u16) -> BigNever { + // CHECK: call void @llvm.trap + mir!{ + { + RET = CastTransmute(x); + Return() + } + } +} + +// CHECK-LABEL: @check_from_uninhabited( +#[no_mangle] +#[custom_mir(dialect = "runtime", phase = "initial")] +pub unsafe fn check_from_uninhabited(x: BigNever) -> u16 { + // CHECK: ret i16 poison + mir!{ + { + RET = CastTransmute(x); + Return() + } + } +} + +// CHECK-LABEL: @check_intermediate_passthrough( +#[no_mangle] +pub unsafe fn check_intermediate_passthrough(x: u32) -> i32 { + // CHECK: start + // CHECK: %[[TMP:.+]] = add i32 1, %x + // CHECK: %[[RET:.+]] = add i32 %[[TMP]], 1 + // CHECK: ret i32 %[[RET]] + unsafe { + transmute::<u32, i32>(1 + x) + 1 + } +} + +// CHECK-LABEL: @check_nop_pair( +#[no_mangle] +pub unsafe fn check_nop_pair(x: (u8, i8)) -> (i8, u8) { + // CHECK-NOT: alloca + // CHECK: %0 = insertvalue { i8, i8 } poison, i8 %x.0, 0 + // CHECK: %1 = insertvalue { i8, i8 } %0, i8 %x.1, 1 + // CHECK: ret { i8, i8 } %1 + unsafe { + transmute(x) + } +} + +// CHECK-LABEL: @check_to_newtype( +#[no_mangle] +pub unsafe fn check_to_newtype(x: u64) -> Scalar64 { + // CHECK-NOT: alloca + // CHECK: ret i64 %x + transmute(x) +} + +// CHECK-LABEL: @check_from_newtype( +#[no_mangle] +pub unsafe fn check_from_newtype(x: Scalar64) -> u64 { + // CHECK-NOT: alloca + // CHECK: ret i64 %x + transmute(x) +} + +// CHECK-LABEL: @check_aggregate_to_bool( +#[no_mangle] +pub unsafe fn check_aggregate_to_bool(x: Aggregate8) -> bool { + // CHECK: %x = alloca %Aggregate8, align 1 + // CHECK: %[[BYTE:.+]] = load i8, ptr %x, align 1 + // CHECK: %[[BOOL:.+]] = trunc i8 %[[BYTE]] to i1 + // CHECK: ret i1 %[[BOOL]] + transmute(x) +} + +// CHECK-LABEL: @check_aggregate_from_bool( +#[no_mangle] +pub unsafe fn check_aggregate_from_bool(x: bool) -> Aggregate8 { + // CHECK: %0 = alloca %Aggregate8, align 1 + // CHECK: %[[BYTE:.+]] = zext i1 %x to i8 + // CHECK: store i8 %[[BYTE]], ptr %0, align 1 + transmute(x) +} + +// CHECK-LABEL: @check_byte_to_bool( +#[no_mangle] +pub unsafe fn check_byte_to_bool(x: u8) -> bool { + // CHECK-NOT: alloca + // CHECK: %0 = trunc i8 %x to i1 + // CHECK: ret i1 %0 + transmute(x) +} + +// CHECK-LABEL: @check_byte_from_bool( +#[no_mangle] +pub unsafe fn check_byte_from_bool(x: bool) -> u8 { + // CHECK-NOT: alloca + // CHECK: %0 = zext i1 %x to i8 + // CHECK: ret i8 %0 + transmute(x) +} + +// CHECK-LABEL: @check_to_pair( +#[no_mangle] +pub unsafe fn check_to_pair(x: u64) -> Option<i32> { + // CHECK: %0 = alloca { i32, i32 }, align 4 + // CHECK: store i64 %x, ptr %0, align 4 + transmute(x) +} + +// CHECK-LABEL: @check_from_pair( +#[no_mangle] +pub unsafe fn check_from_pair(x: Option<i32>) -> u64 { + // The two arguments are of types that are only 4-aligned, but they're + // immediates so we can write using the destination alloca's alignment. + const { assert!(std::mem::align_of::<Option<i32>>() == 4) }; + + // CHECK: %0 = alloca i64, align 8 + // CHECK: store i32 %x.0, ptr %1, align 8 + // CHECK: store i32 %x.1, ptr %2, align 4 + // CHECK: %3 = load i64, ptr %0, align 8 + // CHECK: ret i64 %3 + transmute(x) +} + +// CHECK-LABEL: @check_to_float( +#[no_mangle] +pub unsafe fn check_to_float(x: u32) -> f32 { + // CHECK-NOT: alloca + // CHECK: %0 = bitcast i32 %x to float + // CHECK: ret float %0 + transmute(x) +} + +// CHECK-LABEL: @check_from_float( +#[no_mangle] +pub unsafe fn check_from_float(x: f32) -> u32 { + // CHECK-NOT: alloca + // CHECK: %0 = bitcast float %x to i32 + // CHECK: ret i32 %0 + transmute(x) +} + +// CHECK-LABEL: @check_to_bytes( +#[no_mangle] +pub unsafe fn check_to_bytes(x: u32) -> [u8; 4] { + // CHECK: %0 = alloca [4 x i8], align 1 + // CHECK: store i32 %x, ptr %0, align 1 + transmute(x) +} + +// CHECK-LABEL: @check_from_bytes( +#[no_mangle] +pub unsafe fn check_from_bytes(x: [u8; 4]) -> u32 { + // CHECK: %x = alloca [4 x i8], align 1 + // CHECK: %[[VAL:.+]] = load i32, ptr %x, align 1 + // CHECK: ret i32 %[[VAL]] + transmute(x) +} + +// CHECK-LABEL: @check_to_aggregate( +#[no_mangle] +pub unsafe fn check_to_aggregate(x: u64) -> Aggregate64 { + // CHECK: %0 = alloca %Aggregate64, align 4 + // CHECK: store i64 %x, ptr %0, align 4 + // CHECK: %1 = load i64, ptr %0, align 4 + // CHECK: ret i64 %1 + transmute(x) +} + +// CHECK-LABEL: @check_from_aggregate( +#[no_mangle] +pub unsafe fn check_from_aggregate(x: Aggregate64) -> u64 { + // CHECK: %x = alloca %Aggregate64, align 4 + // CHECK: %[[VAL:.+]] = load i64, ptr %x, align 4 + // CHECK: ret i64 %[[VAL]] + transmute(x) +} + +// CHECK-LABEL: @check_long_array_less_aligned( +#[no_mangle] +pub unsafe fn check_long_array_less_aligned(x: [u64; 100]) -> [u16; 400] { + // CHECK-NEXT: start + // CHECK-NEXT: call void @llvm.memcpy.p0.p0.i64(ptr align 2 %0, ptr align 8 %x, i64 800, i1 false) + // CHECK-NEXT: ret void + transmute(x) +} + +// CHECK-LABEL: @check_long_array_more_aligned( +#[no_mangle] +pub unsafe fn check_long_array_more_aligned(x: [u8; 100]) -> [u32; 25] { + // CHECK-NEXT: start + // CHECK-NEXT: call void @llvm.memcpy.p0.p0.i64(ptr align 4 %0, ptr align 1 %x, i64 100, i1 false) + // CHECK-NEXT: ret void + transmute(x) +} + +// CHECK-LABEL: @check_pair_with_bool( +#[no_mangle] +pub unsafe fn check_pair_with_bool(x: (u8, bool)) -> (bool, i8) { + // CHECK-NOT: alloca + // CHECK: trunc i8 %x.0 to i1 + // CHECK: zext i1 %x.1 to i8 + transmute(x) +} + +// CHECK-LABEL: @check_float_to_pointer( +#[no_mangle] +pub unsafe fn check_float_to_pointer(x: f64) -> *const () { + // CHECK-NOT: alloca + // CHECK: %0 = bitcast double %x to i64 + // CHECK: %1 = inttoptr i64 %0 to ptr + // CHECK: ret ptr %1 + transmute(x) +} + +// CHECK-LABEL: @check_float_from_pointer( +#[no_mangle] +pub unsafe fn check_float_from_pointer(x: *const ()) -> f64 { + // CHECK-NOT: alloca + // CHECK: %0 = ptrtoint ptr %x to i64 + // CHECK: %1 = bitcast i64 %0 to double + // CHECK: ret double %1 + transmute(x) +} + +// CHECK-LABEL: @check_array_to_pair( +#[no_mangle] +pub unsafe fn check_array_to_pair(x: [u8; 16]) -> (i64, u64) { + // CHECK-NOT: alloca + // CHECK: %[[FST:.+]] = load i64, ptr %{{.+}}, align 1, !noundef ! + // CHECK: %[[SND:.+]] = load i64, ptr %{{.+}}, align 1, !noundef ! + // CHECK: %[[PAIR0:.+]] = insertvalue { i64, i64 } poison, i64 %[[FST]], 0 + // CHECK: %[[PAIR01:.+]] = insertvalue { i64, i64 } %[[PAIR0]], i64 %[[SND]], 1 + // CHECK: ret { i64, i64 } %[[PAIR01]] + transmute(x) +} + +// CHECK-LABEL: @check_pair_to_array( +#[no_mangle] +pub unsafe fn check_pair_to_array(x: (i64, u64)) -> [u8; 16] { + // CHECK-NOT: alloca + // CHECK: store i64 %x.0, ptr %{{.+}}, align 1 + // CHECK: store i64 %x.1, ptr %{{.+}}, align 1 + transmute(x) +} + +// CHECK-LABEL: @check_heterogeneous_integer_pair( +#[no_mangle] +pub unsafe fn check_heterogeneous_integer_pair(x: (i32, bool)) -> (bool, u32) { + // CHECK: store i32 %x.0 + // CHECK: %[[WIDER:.+]] = zext i1 %x.1 to i8 + // CHECK: store i8 %[[WIDER]] + + // CHECK: %[[BYTE:.+]] = load i8 + // CHECK: trunc i8 %[[BYTE:.+]] to i1 + // CHECK: load i32 + transmute(x) +} + +// CHECK-LABEL: @check_heterogeneous_float_pair( +#[no_mangle] +pub unsafe fn check_heterogeneous_float_pair(x: (f64, f32)) -> (f32, f64) { + // CHECK: store double %x.0 + // CHECK: store float %x.1 + // CHECK: %[[A:.+]] = load float + // CHECK: %[[B:.+]] = load double + // CHECK: %[[P:.+]] = insertvalue { float, double } poison, float %[[A]], 0 + // CHECK: insertvalue { float, double } %[[P]], double %[[B]], 1 + transmute(x) +} + +// CHECK-LABEL: @check_issue_110005( +#[no_mangle] +pub unsafe fn check_issue_110005(x: (usize, bool)) -> Option<Box<[u8]>> { + // CHECK: store i64 %x.0 + // CHECK: %[[WIDER:.+]] = zext i1 %x.1 to i8 + // CHECK: store i8 %[[WIDER]] + // CHECK: load ptr + // CHECK: load i64 + transmute(x) +} + +// CHECK-LABEL: @check_pair_to_dst_ref( +#[no_mangle] +pub unsafe fn check_pair_to_dst_ref<'a>(x: (usize, usize)) -> &'a [u8] { + // CHECK: %0 = inttoptr i64 %x.0 to ptr + // CHECK: %1 = insertvalue { ptr, i64 } poison, ptr %0, 0 + // CHECK: %2 = insertvalue { ptr, i64 } %1, i64 %x.1, 1 + // CHECK: ret { ptr, i64 } %2 + transmute(x) +} + +// CHECK-LABEL: @check_issue_109992( +#[no_mangle] +#[custom_mir(dialect = "runtime", phase = "optimized")] +pub unsafe fn check_issue_109992(x: ()) -> [(); 1] { + // This uses custom MIR to avoid MIR optimizations having removed ZST ops. + + // CHECK: start + // CHECK-NEXT: ret void + mir!{ + { + RET = CastTransmute(x); + Return() + } + } +} + +// CHECK-LABEL: @check_maybe_uninit_pair(i16 %x.0, i64 %x.1) +#[no_mangle] +pub unsafe fn check_maybe_uninit_pair( + x: (MaybeUninit<u16>, MaybeUninit<u64>), +) -> (MaybeUninit<i64>, MaybeUninit<i16>) { + // Thanks to `MaybeUninit` this is actually defined behaviour, + // unlike the examples above with pairs of primitives. + + // CHECK: store i16 %x.0 + // CHECK: store i64 %x.1 + // CHECK: load i64 + // CHECK-NOT: noundef + // CHECK: load i16 + // CHECK-NOT: noundef + // CHECK: ret { i64, i16 } + transmute(x) +} + +#[repr(align(8))] +pub struct HighAlignScalar(u8); + +// CHECK-LABEL: @check_to_overalign( +#[no_mangle] +pub unsafe fn check_to_overalign(x: u64) -> HighAlignScalar { + // CHECK: %0 = alloca %HighAlignScalar, align 8 + // CHECK: store i64 %x, ptr %0, align 8 + // CHECK: %1 = load i64, ptr %0, align 8 + // CHECK: ret i64 %1 + transmute(x) +} + +// CHECK-LABEL: @check_from_overalign( +#[no_mangle] +pub unsafe fn check_from_overalign(x: HighAlignScalar) -> u64 { + // CHECK: %x = alloca %HighAlignScalar, align 8 + // CHECK: %[[VAL:.+]] = load i64, ptr %x, align 8 + // CHECK: ret i64 %[[VAL]] + transmute(x) +} |