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[test][instcombine] Add test cases for all x.with.overflow overflow checks

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For each of the x.with.overflow variants, if only the overflow bit is consumed, we can generate a direct overflow comparison.  This precommits tests for each of the variants and tries to cover interesting cornercases.
This commit is contained in:
Philip Reames 2021-06-23 18:50:00 -07:00
parent 36b5d3f1af
commit b215117634
5 changed files with 425 additions and 0 deletions
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103
test/Transforms/InstCombine/saddo.ll Normal file
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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -instcombine -S | FileCheck %s
declare { i64, i1 } @llvm.sadd.with.overflow.i64(i64, i64)
declare { i8, i1 } @llvm.sadd.with.overflow.i8(i8, i8)
define i1 @test_generic(i64 %a, i64 %b) {
; CHECK-LABEL: @test_generic(
; CHECK-NEXT: [[RES:%.*]] = tail call { i64, i1 } @llvm.sadd.with.overflow.i64(i64 [[A:%.*]], i64 [[B:%.*]])
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i64, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i64, i1 } @llvm.sadd.with.overflow.i64(i64 %a, i64 %b)
%overflow = extractvalue { i64, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant0(i8 %a) {
; CHECK-LABEL: @test_constant0(
; CHECK-NEXT: ret i1 false
;
%res = tail call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 %a, i8 0)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant1(i8 %a) {
; CHECK-LABEL: @test_constant1(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 [[A:%.*]], i8 1)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 %a, i8 1)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant2(i8 %a) {
; CHECK-LABEL: @test_constant2(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 [[A:%.*]], i8 2)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 %a, i8 2)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant3(i8 %a) {
; CHECK-LABEL: @test_constant3(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 [[A:%.*]], i8 3)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 %a, i8 3)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant4(i8 %a) {
; CHECK-LABEL: @test_constant4(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 [[A:%.*]], i8 4)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 %a, i8 4)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant127(i8 %a) {
; CHECK-LABEL: @test_constant127(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 [[A:%.*]], i8 127)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 %a, i8 127)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant128(i8 %a) {
; CHECK-LABEL: @test_constant128(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 [[A:%.*]], i8 -128)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 %a, i8 128)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant255(i8 %a) {
; CHECK-LABEL: @test_constant255(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 [[A:%.*]], i8 -1)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 %a, i8 255)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}

102
test/Transforms/InstCombine/smulo.ll Normal file
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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -instcombine -S | FileCheck %s
declare { i64, i1 } @llvm.smul.with.overflow.i64(i64, i64)
declare { i8, i1 } @llvm.smul.with.overflow.i8(i8, i8)
define i1 @test_generic(i64 %a, i64 %b) {
; CHECK-LABEL: @test_generic(
; CHECK-NEXT: [[RES:%.*]] = tail call { i64, i1 } @llvm.smul.with.overflow.i64(i64 [[A:%.*]], i64 [[B:%.*]])
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i64, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i64, i1 } @llvm.smul.with.overflow.i64(i64 %a, i64 %b)
%overflow = extractvalue { i64, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant0(i8 %a) {
; CHECK-LABEL: @test_constant0(
; CHECK-NEXT: ret i1 false
;
%res = tail call { i8, i1 } @llvm.smul.with.overflow.i8(i8 %a, i8 0)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant1(i8 %a) {
; CHECK-LABEL: @test_constant1(
; CHECK-NEXT: ret i1 false
;
%res = tail call { i8, i1 } @llvm.smul.with.overflow.i8(i8 %a, i8 1)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant2(i8 %a) {
; CHECK-LABEL: @test_constant2(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.smul.with.overflow.i8(i8 [[A:%.*]], i8 2)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.smul.with.overflow.i8(i8 %a, i8 2)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant3(i8 %a) {
; CHECK-LABEL: @test_constant3(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.smul.with.overflow.i8(i8 [[A:%.*]], i8 3)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.smul.with.overflow.i8(i8 %a, i8 3)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant4(i8 %a) {
; CHECK-LABEL: @test_constant4(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.smul.with.overflow.i8(i8 [[A:%.*]], i8 4)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.smul.with.overflow.i8(i8 %a, i8 4)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant127(i8 %a) {
; CHECK-LABEL: @test_constant127(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.smul.with.overflow.i8(i8 [[A:%.*]], i8 127)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.smul.with.overflow.i8(i8 %a, i8 127)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant128(i8 %a) {
; CHECK-LABEL: @test_constant128(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.smul.with.overflow.i8(i8 [[A:%.*]], i8 -128)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.smul.with.overflow.i8(i8 %a, i8 128)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant255(i8 %a) {
; CHECK-LABEL: @test_constant255(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.smul.with.overflow.i8(i8 [[A:%.*]], i8 -1)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.smul.with.overflow.i8(i8 %a, i8 255)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}

104
test/Transforms/InstCombine/ssubo.ll Normal file
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@ -0,0 +1,104 @@
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -instcombine -S | FileCheck %s
declare { i64, i1 } @llvm.ssub.with.overflow.i64(i64, i64)
declare { i8, i1 } @llvm.ssub.with.overflow.i8(i8, i8)
define i1 @test_generic(i64 %a, i64 %b) {
; CHECK-LABEL: @test_generic(
; CHECK-NEXT: [[RES:%.*]] = tail call { i64, i1 } @llvm.ssub.with.overflow.i64(i64 [[A:%.*]], i64 [[B:%.*]])
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i64, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i64, i1 } @llvm.ssub.with.overflow.i64(i64 %a, i64 %b)
%overflow = extractvalue { i64, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant0(i8 %a) {
; CHECK-LABEL: @test_constant0(
; CHECK-NEXT: ret i1 false
;
%res = tail call { i8, i1 } @llvm.ssub.with.overflow.i8(i8 %a, i8 0)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant1(i8 %a) {
; CHECK-LABEL: @test_constant1(
; CHECK-NEXT: [[TMP1:%.*]] = call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 [[A:%.*]], i8 -1)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[TMP1]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.ssub.with.overflow.i8(i8 %a, i8 1)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant2(i8 %a) {
; CHECK-LABEL: @test_constant2(
; CHECK-NEXT: [[TMP1:%.*]] = call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 [[A:%.*]], i8 -2)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[TMP1]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.ssub.with.overflow.i8(i8 %a, i8 2)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant3(i8 %a) {
; CHECK-LABEL: @test_constant3(
; CHECK-NEXT: [[TMP1:%.*]] = call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 [[A:%.*]], i8 -3)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[TMP1]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.ssub.with.overflow.i8(i8 %a, i8 3)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant4(i8 %a) {
; CHECK-LABEL: @test_constant4(
; CHECK-NEXT: [[TMP1:%.*]] = call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 [[A:%.*]], i8 -4)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[TMP1]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.ssub.with.overflow.i8(i8 %a, i8 4)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant127(i8 %a) {
; CHECK-LABEL: @test_constant127(
; CHECK-NEXT: [[TMP1:%.*]] = call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 [[A:%.*]], i8 -127)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[TMP1]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.ssub.with.overflow.i8(i8 %a, i8 127)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant128(i8 %a) {
; CHECK-LABEL: @test_constant128(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.ssub.with.overflow.i8(i8 [[A:%.*]], i8 -128)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.ssub.with.overflow.i8(i8 %a, i8 128)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant255(i8 %a) {
; CHECK-LABEL: @test_constant255(
; CHECK-NEXT: [[TMP1:%.*]] = call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 [[A:%.*]], i8 1)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[TMP1]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.ssub.with.overflow.i8(i8 %a, i8 255)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}

12
test/Transforms/InstCombine/umulo.ll
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@ -55,6 +55,18 @@ define i1 @test_constant3(i8 %a) {
ret i1 %overflow
}
define i1 @test_constant4(i8 %a) {
; CHECK-LABEL: @test_constant4(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.umul.with.overflow.i8(i8 [[A:%.*]], i8 4)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.umul.with.overflow.i8(i8 %a, i8 4)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant127(i8 %a) {
; CHECK-LABEL: @test_constant127(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.umul.with.overflow.i8(i8 [[A:%.*]], i8 127)

104
test/Transforms/InstCombine/usubo.ll Normal file
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@ -0,0 +1,104 @@
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -instcombine -S | FileCheck %s
declare { i64, i1 } @llvm.usub.with.overflow.i64(i64, i64)
declare { i8, i1 } @llvm.usub.with.overflow.i8(i8, i8)
define i1 @test_generic(i64 %a, i64 %b) {
; CHECK-LABEL: @test_generic(
; CHECK-NEXT: [[RES:%.*]] = tail call { i64, i1 } @llvm.usub.with.overflow.i64(i64 [[A:%.*]], i64 [[B:%.*]])
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i64, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i64, i1 } @llvm.usub.with.overflow.i64(i64 %a, i64 %b)
%overflow = extractvalue { i64, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant0(i8 %a) {
; CHECK-LABEL: @test_constant0(
; CHECK-NEXT: ret i1 false
;
%res = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 %a, i8 0)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant1(i8 %a) {
; CHECK-LABEL: @test_constant1(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 [[A:%.*]], i8 1)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 %a, i8 1)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant2(i8 %a) {
; CHECK-LABEL: @test_constant2(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 [[A:%.*]], i8 2)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 %a, i8 2)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant3(i8 %a) {
; CHECK-LABEL: @test_constant3(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 [[A:%.*]], i8 3)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 %a, i8 3)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant4(i8 %a) {
; CHECK-LABEL: @test_constant4(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 [[A:%.*]], i8 4)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 %a, i8 4)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant127(i8 %a) {
; CHECK-LABEL: @test_constant127(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 [[A:%.*]], i8 127)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 %a, i8 127)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant128(i8 %a) {
; CHECK-LABEL: @test_constant128(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 [[A:%.*]], i8 -128)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 %a, i8 128)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}
define i1 @test_constant255(i8 %a) {
; CHECK-LABEL: @test_constant255(
; CHECK-NEXT: [[RES:%.*]] = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 [[A:%.*]], i8 -1)
; CHECK-NEXT: [[OVERFLOW:%.*]] = extractvalue { i8, i1 } [[RES]], 1
; CHECK-NEXT: ret i1 [[OVERFLOW]]
;
%res = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 %a, i8 255)
%overflow = extractvalue { i8, i1 } %res, 1
ret i1 %overflow
}