9ca2c309ab
We can only fold insertvalue undef, (extractvalue x, n) to x if x is not poison, otherwise we might be replacing undef with poison (https://alive2.llvm.org/ce/z/fnw3c8). The insertvalue poison case is always fine. I didn't go to particularly large effort to preserve cases where folding with undef is still legal (mainly when there is a chain of multiple inserts that end up covering the whole aggregate), because this shouldn't really occur in practice: We should always be generating the insertvalue poison form when constructing aggregates nowadays. Differential Revision: https://reviews.llvm.org/D144106
57 lines
1.7 KiB
LLVM
57 lines
1.7 KiB
LLVM
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
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; RUN: opt < %s -passes=instsimplify -S | FileCheck %s
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define {i32, i32} @insert_poison({i32, i32} %x) {
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; CHECK-LABEL: @insert_poison(
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; CHECK-NEXT: ret { i32, i32 } [[X:%.*]]
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;
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%v = insertvalue {i32, i32} %x, i32 poison, 0
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ret {i32, i32} %v
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}
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define {i32, i32} @insert_undef({i32, i32} %x) {
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; CHECK-LABEL: @insert_undef(
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; CHECK-NEXT: [[V:%.*]] = insertvalue { i32, i32 } [[X:%.*]], i32 undef, 0
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; CHECK-NEXT: ret { i32, i32 } [[V]]
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;
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%v = insertvalue {i32, i32} %x, i32 undef, 0
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ret {i32, i32} %v
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}
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define {i32, i32} @insert_undef_into_non_poison({i32, i32} noundef %x) {
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; CHECK-LABEL: @insert_undef_into_non_poison(
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; CHECK-NEXT: ret { i32, i32 } [[X:%.*]]
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;
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%v = insertvalue {i32, i32} %x, i32 undef, 0
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ret {i32, i32} %v
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}
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define {i32, i32} @insert_into_poison({i32, i32} %x) {
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; CHECK-LABEL: @insert_into_poison(
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; CHECK-NEXT: ret { i32, i32 } [[X:%.*]]
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;
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%elem = extractvalue {i32, i32} %x, 0
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%v = insertvalue {i32, i32} poison, i32 %elem, 0
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ret {i32, i32} %v
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}
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define {i32, i32} @insert_into_undef({i32, i32} %x) {
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; CHECK-LABEL: @insert_into_undef(
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; CHECK-NEXT: [[ELEM:%.*]] = extractvalue { i32, i32 } [[X:%.*]], 0
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; CHECK-NEXT: [[V:%.*]] = insertvalue { i32, i32 } undef, i32 [[ELEM]], 0
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; CHECK-NEXT: ret { i32, i32 } [[V]]
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;
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%elem = extractvalue {i32, i32} %x, 0
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%v = insertvalue {i32, i32} undef, i32 %elem, 0
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ret {i32, i32} %v
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}
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define {i32, i32} @insert_non_poison_into_undef({i32, i32} noundef %x) {
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; CHECK-LABEL: @insert_non_poison_into_undef(
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; CHECK-NEXT: ret { i32, i32 } [[X:%.*]]
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;
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%elem = extractvalue {i32, i32} %x, 0
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%v = insertvalue {i32, i32} undef, i32 %elem, 0
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ret {i32, i32} %v
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}
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