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b8df869ebb
When outputs are used together with labels, they are considered to be written for all destinations, not only when falling through.
54 lines
1.7 KiB
Rust
54 lines
1.7 KiB
Rust
//@ compile-flags: -O
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//@ only-x86_64
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#![crate_type = "rlib"]
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#![feature(asm_goto)]
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use std::arch::asm;
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// CHECK-LABEL: @asm_goto
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#[no_mangle]
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pub unsafe fn asm_goto() {
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// CHECK: callbr void asm sideeffect alignstack inteldialect "
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// CHECK-NEXT: to label %[[FALLTHROUGHBB:[a-b0-9]+]] [label %[[JUMPBB:[a-b0-9]+]]]
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asm!("jmp {}", label {});
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}
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// CHECK-LABEL: @asm_goto_with_outputs
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#[no_mangle]
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pub unsafe fn asm_goto_with_outputs() -> u64 {
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let out: u64;
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// CHECK: [[RES:%[0-9]+]] = callbr i64 asm sideeffect alignstack inteldialect "
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// CHECK-NEXT: to label %[[FALLTHROUGHBB:[a-b0-9]+]] [label %[[JUMPBB:[a-b0-9]+]]]
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asm!("{} /* {} */", out(reg) out, label { return 1; });
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// CHECK: [[JUMPBB]]:
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// CHECK-NEXT: [[RET:%.+]] = phi i64 [ [[RES]], %[[FALLTHROUGHBB]] ], [ 1, %start ]
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// CHECK-NEXT: ret i64 [[RET]]
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out
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}
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// CHECK-LABEL: @asm_goto_with_outputs_use_in_label
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#[no_mangle]
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pub unsafe fn asm_goto_with_outputs_use_in_label() -> u64 {
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let out: u64;
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// CHECK: [[RES:%[0-9]+]] = callbr i64 asm sideeffect alignstack inteldialect "
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// CHECK-NEXT: to label %[[FALLTHROUGHBB:[a-b0-9]+]] [label %[[JUMPBB:[a-b0-9]+]]]
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asm!("{} /* {} */", out(reg) out, label { return out; });
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// CHECK: [[JUMPBB]]:
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// CHECK-NEXT: [[RET:%.+]] = phi i64 [ 1, %[[FALLTHROUGHBB]] ], [ [[RES]], %start ]
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// CHECK-NEXT: ret i64 [[RET]]
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1
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}
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// CHECK-LABEL: @asm_goto_noreturn
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#[no_mangle]
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pub unsafe fn asm_goto_noreturn() -> u64 {
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let out: u64;
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// CHECK: callbr void asm sideeffect alignstack inteldialect "
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// CHECK-NEXT: to label %unreachable [label %[[JUMPBB:[a-b0-9]+]]]
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asm!("jmp {}", label { return 1; }, options(noreturn));
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// CHECK: [[JUMPBB]]:
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// CHECK-NEXT: ret i64 1
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out
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}
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