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75 lines
2.9 KiB
Rust
75 lines
2.9 KiB
Rust
// Ensure the asm for array comparisons is properly optimized.
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//@ compile-flags: -C opt-level=2
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//@ needs-deterministic-layouts (checks depend on tuple layout)
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#![crate_type = "lib"]
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// CHECK-LABEL: @compare
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// CHECK: start:
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// CHECK-NEXT: ret i1 true
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#[no_mangle]
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pub fn compare() -> bool {
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let bytes = 12.5f32.to_ne_bytes();
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bytes
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== if cfg!(target_endian = "big") {
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[0x41, 0x48, 0x00, 0x00]
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} else {
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[0x00, 0x00, 0x48, 0x41]
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}
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}
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// CHECK-LABEL: @array_of_tuple_le
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#[no_mangle]
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pub fn array_of_tuple_le(a: &[(i16, u16); 2], b: &[(i16, u16); 2]) -> bool {
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// Ensure that, after all the optimizations have run, the happy path just checks
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// `eq` on each corresponding pair and moves onto the next one if it is.
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// Then there's a dedup'd comparison for the place that's different.
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// (As opposed to, say, running a full `[su]cmp` as part of checking equality.)
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// This is written quite specifically because different library code was triggering
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// <https://github.com/llvm/llvm-project/issues/132678> along the way, so this
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// has enough checks to make sure that's not happening. It doesn't need to be
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// *exactly* this IR, but be careful if you ever need to update these checks.
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// CHECK: start:
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// CHECK: %[[A00:.+]] = load i16, ptr %a
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// CHECK: %[[B00:.+]] = load i16, ptr %b
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// CHECK-NOT: cmp
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// CHECK: %[[EQ00:.+]] = icmp eq i16 %[[A00]], %[[B00]]
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// CHECK-NEXT: br i1 %[[EQ00]], label %[[L01:.+]], label %[[EXIT_S:.+]]
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// CHECK: [[L01]]:
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// CHECK: %[[PA01:.+]] = getelementptr{{.+}}i8, ptr %a, {{i32|i64}} 2
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// CHECK: %[[PB01:.+]] = getelementptr{{.+}}i8, ptr %b, {{i32|i64}} 2
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// CHECK: %[[A01:.+]] = load i16, ptr %[[PA01]]
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// CHECK: %[[B01:.+]] = load i16, ptr %[[PB01]]
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// CHECK-NOT: cmp
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// CHECK: %[[EQ01:.+]] = icmp eq i16 %[[A01]], %[[B01]]
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// CHECK-NEXT: br i1 %[[EQ01]], label %[[L10:.+]], label %[[EXIT_U:.+]]
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// CHECK: [[L10]]:
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// CHECK: %[[PA10:.+]] = getelementptr{{.+}}i8, ptr %a, {{i32|i64}} 4
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// CHECK: %[[PB10:.+]] = getelementptr{{.+}}i8, ptr %b, {{i32|i64}} 4
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// CHECK: %[[A10:.+]] = load i16, ptr %[[PA10]]
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// CHECK: %[[B10:.+]] = load i16, ptr %[[PB10]]
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// CHECK-NOT: cmp
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// CHECK: %[[EQ10:.+]] = icmp eq i16 %[[A10]], %[[B10]]
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// CHECK-NEXT: br i1 %[[EQ10]], label %[[L11:.+]], label %[[EXIT_S]]
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// CHECK: [[L11]]:
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// CHECK: %[[PA11:.+]] = getelementptr{{.+}}i8, ptr %a, {{i32|i64}} 6
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// CHECK: %[[PB11:.+]] = getelementptr{{.+}}i8, ptr %b, {{i32|i64}} 6
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// CHECK: %[[A11:.+]] = load i16, ptr %[[PA11]]
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// CHECK: %[[B11:.+]] = load i16, ptr %[[PB11]]
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// CHECK-NOT: cmp
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// CHECK: %[[EQ11:.+]] = icmp eq i16 %[[A11]], %[[B11]]
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// CHECK-NEXT: br i1 %[[EQ11]], label %[[DONE:.+]], label %[[EXIT_U]]
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// CHECK: [[DONE]]:
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// CHECK: %[[RET:.+]] = phi i1 [ %{{.+}}, %[[EXIT_S]] ], [ %{{.+}}, %[[EXIT_U]] ], [ true, %[[L11]] ]
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// CHECK: ret i1 %[[RET]]
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a <= b
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}
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