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			97 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			97 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
// compile-flags: -O -Z merge-functions=disabled
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// no-system-llvm
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// ignore-debug (the extra assertions get in the way)
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#![crate_type = "lib"]
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// Ensure that various forms of reading pointers correctly annotate the `load`s
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// with `!noundef` and `!range` metadata to enable extra optimization.
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use std::mem::MaybeUninit;
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// CHECK-LABEL: define {{(dso_local )?}}noundef i8 @copy_byte(
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#[no_mangle]
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pub unsafe fn copy_byte(p: *const u8) -> u8 {
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    // CHECK-NOT: load
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    // CHECK: load i8, ptr %p, align 1
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    // CHECK-SAME: !noundef !
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    // CHECK-NOT: load
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    *p
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}
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// CHECK-LABEL: define {{(dso_local )?}}noundef i8 @read_byte(
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#[no_mangle]
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pub unsafe fn read_byte(p: *const u8) -> u8 {
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    // CHECK-NOT: load
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    // CHECK: load i8, ptr %p, align 1
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    // CHECK-SAME: !noundef !
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    // CHECK-NOT: load
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    p.read()
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}
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// CHECK-LABEL: define {{(dso_local )?}}i8 @read_byte_maybe_uninit(
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#[no_mangle]
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pub unsafe fn read_byte_maybe_uninit(p: *const MaybeUninit<u8>) -> MaybeUninit<u8> {
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    // CHECK-NOT: load
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    // CHECK: load i8, ptr %p, align 1
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    // CHECK-NOT: noundef
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    // CHECK-NOT: load
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    p.read()
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}
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// CHECK-LABEL: define {{(dso_local )?}}noundef i8 @read_byte_assume_init(
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#[no_mangle]
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pub unsafe fn read_byte_assume_init(p: &MaybeUninit<u8>) -> u8 {
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    // CHECK-NOT: load
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    // CHECK: load i8, ptr %p, align 1
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    // CHECK-SAME: !noundef !
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    // CHECK-NOT: load
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    p.assume_init_read()
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}
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// CHECK-LABEL: define {{(dso_local )?}}noundef i32 @copy_char(
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#[no_mangle]
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pub unsafe fn copy_char(p: *const char) -> char {
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    // CHECK-NOT: load
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    // CHECK: load i32, ptr %p
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    // CHECK-SAME: !range ![[RANGE:[0-9]+]]
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    // CHECK-SAME: !noundef !
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    // CHECK-NOT: load
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    *p
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}
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// CHECK-LABEL: define {{(dso_local )?}}noundef i32 @read_char(
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#[no_mangle]
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pub unsafe fn read_char(p: *const char) -> char {
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    // CHECK-NOT: load
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    // CHECK: load i32, ptr %p
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    // CHECK-SAME: !range ![[RANGE]]
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    // CHECK-SAME: !noundef !
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    // CHECK-NOT: load
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    p.read()
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}
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// CHECK-LABEL: define {{(dso_local )?}}i32 @read_char_maybe_uninit(
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#[no_mangle]
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pub unsafe fn read_char_maybe_uninit(p: *const MaybeUninit<char>) -> MaybeUninit<char> {
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    // CHECK-NOT: load
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    // CHECK: load i32, ptr %p
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    // CHECK-NOT: range
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    // CHECK-NOT: noundef
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    // CHECK-NOT: load
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    p.read()
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}
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// CHECK-LABEL: define {{(dso_local )?}}noundef i32 @read_char_assume_init(
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#[no_mangle]
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pub unsafe fn read_char_assume_init(p: &MaybeUninit<char>) -> char {
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    // CHECK-NOT: load
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    // CHECK: load i32, ptr %p
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    // CHECK-SAME: !range ![[RANGE]]
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    // CHECK-SAME: !noundef !
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    // CHECK-NOT: load
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    p.assume_init_read()
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}
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// CHECK: ![[RANGE]] = !{i32 0, i32 1114112}
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