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70 lines
2.1 KiB
Rust
70 lines
2.1 KiB
Rust
// compile-flags: -O
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// ignore-debug (because unchecked is checked in debug)
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#![crate_type = "lib"]
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#![feature(unchecked_math)]
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// CHECK-LABEL: @unchecked_shl_unsigned_same
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#[no_mangle]
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pub unsafe fn unchecked_shl_unsigned_same(a: u32, b: u32) -> u32 {
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// CHECK-NOT: assume
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// CHECK-NOT: and i32
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// CHECK: shl i32 %a, %b
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// CHECK-NOT: and i32
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a.unchecked_shl(b)
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}
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// CHECK-LABEL: @unchecked_shl_unsigned_smaller
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#[no_mangle]
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pub unsafe fn unchecked_shl_unsigned_smaller(a: u16, b: u32) -> u16 {
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// This uses -DAG to avoid failing on irrelevant reorderings,
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// like emitting the truncation earlier.
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// CHECK-DAG: %[[INRANGE:.+]] = icmp ult i32 %b, 65536
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// CHECK-DAG: tail call void @llvm.assume(i1 %[[INRANGE]])
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// CHECK-DAG: %[[TRUNC:.+]] = trunc i32 %b to i16
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// CHECK-DAG: shl i16 %a, %[[TRUNC]]
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a.unchecked_shl(b)
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}
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// CHECK-LABEL: @unchecked_shl_unsigned_bigger
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#[no_mangle]
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pub unsafe fn unchecked_shl_unsigned_bigger(a: u64, b: u32) -> u64 {
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// CHECK-NOT: assume
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// CHECK: %[[EXT:.+]] = zext i32 %b to i64
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// CHECK: shl i64 %a, %[[EXT]]
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a.unchecked_shl(b)
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}
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// CHECK-LABEL: @unchecked_shr_signed_same
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#[no_mangle]
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pub unsafe fn unchecked_shr_signed_same(a: i32, b: u32) -> i32 {
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// CHECK-NOT: assume
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// CHECK-NOT: and i32
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// CHECK: ashr i32 %a, %b
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// CHECK-NOT: and i32
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a.unchecked_shr(b)
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}
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// CHECK-LABEL: @unchecked_shr_signed_smaller
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#[no_mangle]
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pub unsafe fn unchecked_shr_signed_smaller(a: i16, b: u32) -> i16 {
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// This uses -DAG to avoid failing on irrelevant reorderings,
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// like emitting the truncation earlier.
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// CHECK-DAG: %[[INRANGE:.+]] = icmp ult i32 %b, 32768
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// CHECK-DAG: tail call void @llvm.assume(i1 %[[INRANGE]])
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// CHECK-DAG: %[[TRUNC:.+]] = trunc i32 %b to i16
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// CHECK-DAG: ashr i16 %a, %[[TRUNC]]
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a.unchecked_shr(b)
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}
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// CHECK-LABEL: @unchecked_shr_signed_bigger
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#[no_mangle]
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pub unsafe fn unchecked_shr_signed_bigger(a: i64, b: u32) -> i64 {
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// CHECK-NOT: assume
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// CHECK: %[[EXT:.+]] = zext i32 %b to i64
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// CHECK: ashr i64 %a, %[[EXT]]
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a.unchecked_shr(b)
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}
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