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b5376ba601
I added this back in 111999, but I no longer think it's a good idea - It had to get scaled back to only power-of-two things to not break a bunch of targets - LLVM seems to be getting better at memcpy removal anyway - Introducing vector instructions has seemed to sometimes (115515) make autovectorization worse So this removes it from the codegen crates entirely, and instead just tries to use <https://doc.rust-lang.org/nightly/nightly-rustc/rustc_codegen_ssa/traits/builder/trait.BuilderMethods.html#method.typed_place_copy> instead of direct `memcpy` so things will still use load/store for immediates.
63 lines
2.2 KiB
Rust
63 lines
2.2 KiB
Rust
//@ compile-flags: -O -C no-prepopulate-passes
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#![crate_type = "lib"]
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// CHECK-LABEL: @array_load
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#[no_mangle]
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pub fn array_load(a: &[u8; 4]) -> [u8; 4] {
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// CHECK-NOT: alloca
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// CHECK: %[[ALLOCA:.+]] = alloca [4 x i8], align 1
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// CHECK-NOT: alloca
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// CHECK: call void @llvm.memcpy.{{.+}}(ptr align 1 %[[ALLOCA]], ptr align 1 %a, {{.+}} 4, i1 false)
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// CHECK: %[[TEMP:.+]] = load i32, ptr %[[ALLOCA]], align 1
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// CHECK: ret i32 %[[TEMP]]
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*a
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}
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// CHECK-LABEL: @array_store
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#[no_mangle]
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pub fn array_store(a: [u8; 4], p: &mut [u8; 4]) {
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// CHECK-NOT: alloca
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// CHECK: %[[TEMP:.+]] = alloca i32, [[TEMPALIGN:align [0-9]+]]
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// CHECK-NOT: alloca
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// CHECK: %a = alloca [4 x i8]
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// CHECK-NOT: alloca
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// store i32 %0, ptr %[[TEMP]]
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// CHECK: call void @llvm.memcpy.{{.+}}(ptr align 1 %a, ptr [[TEMPALIGN]] %[[TEMP]], {{.+}} 4, i1 false)
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// CHECK: call void @llvm.memcpy.{{.+}}(ptr align 1 %p, ptr align 1 %a, {{.+}} 4, i1 false)
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*p = a;
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}
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// CHECK-LABEL: @array_copy
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#[no_mangle]
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pub fn array_copy(a: &[u8; 4], p: &mut [u8; 4]) {
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// CHECK-NOT: alloca
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// CHECK: %[[LOCAL:.+]] = alloca [4 x i8], align 1
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// CHECK-NOT: alloca
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// CHECK: call void @llvm.memcpy.{{.+}}(ptr align 1 %[[LOCAL]], ptr align 1 %a, {{.+}} 4, i1 false)
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// CHECK: call void @llvm.memcpy.{{.+}}(ptr align 1 %p, ptr align 1 %[[LOCAL]], {{.+}} 4, i1 false)
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*p = *a;
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}
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// CHECK-LABEL: @array_copy_1_element
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#[no_mangle]
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pub fn array_copy_1_element(a: &[u8; 1], p: &mut [u8; 1]) {
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// CHECK-NOT: alloca
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// CHECK: %[[LOCAL:.+]] = alloca [1 x i8], align 1
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// CHECK-NOT: alloca
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// CHECK: call void @llvm.memcpy.{{.+}}(ptr align 1 %[[LOCAL]], ptr align 1 %a, {{.+}} 1, i1 false)
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// CHECK: call void @llvm.memcpy.{{.+}}(ptr align 1 %p, ptr align 1 %[[LOCAL]], {{.+}} 1, i1 false)
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*p = *a;
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}
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// CHECK-LABEL: @array_copy_2_elements
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#[no_mangle]
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pub fn array_copy_2_elements(a: &[u8; 2], p: &mut [u8; 2]) {
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// CHECK-NOT: alloca
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// CHECK: %[[LOCAL:.+]] = alloca [2 x i8], align 1
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// CHECK-NOT: alloca
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// CHECK: call void @llvm.memcpy.{{.+}}(ptr align 1 %[[LOCAL]], ptr align 1 %a, {{.+}} 2, i1 false)
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// CHECK: call void @llvm.memcpy.{{.+}}(ptr align 1 %p, ptr align 1 %[[LOCAL]], {{.+}} 2, i1 false)
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*p = *a;
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}
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