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; RUN: opt -S -instcombine < %s | FileCheck %s
; <rdar://problem/8558713>
declare void @throwAnExceptionOrWhatever()
; CHECK: @test1
define i32 @test1(i32 %a, i32 %b) nounwind ssp {
entry:
; CHECK-NOT: sext
%conv = sext i32 %a to i64
%conv2 = sext i32 %b to i64
%add = add nsw i64 %conv2, %conv
%add.off = add i64 %add, 2147483648
; CHECK: llvm.sadd.with.overflow.i32
%0 = icmp ugt i64 %add.off, 4294967295
br i1 %0, label %if.then, label %if.end
if.then:
tail call void @throwAnExceptionOrWhatever() nounwind
br label %if.end
if.end:
; CHECK-NOT: trunc
%conv9 = trunc i64 %add to i32
; CHECK: ret i32
ret i32 %conv9
}
; CHECK: @test2
; This form should not be promoted for two reasons: 1) it is unprofitable to
; promote it since the add.off instruction has another use, and 2) it is unsafe
; because the add-with-off makes the high bits of the original add live.
define i32 @test2(i32 %a, i32 %b, i64* %P) nounwind ssp {
entry:
%conv = sext i32 %a to i64
%conv2 = sext i32 %b to i64
%add = add nsw i64 %conv2, %conv
%add.off = add i64 %add, 2147483648
store i64 %add.off, i64* %P
; CHECK-NOT: llvm.sadd.with.overflow
%0 = icmp ugt i64 %add.off, 4294967295
br i1 %0, label %if.then, label %if.end
if.then:
tail call void @throwAnExceptionOrWhatever() nounwind
br label %if.end
if.end:
%conv9 = trunc i64 %add to i32
; CHECK: ret i32
ret i32 %conv9
}
; CHECK: test3
; PR8816
; This is illegal to transform because the high bits of the original add are
; live out.
define i64 @test3(i32 %a, i32 %b) nounwind ssp {
entry:
%conv = sext i32 %a to i64
%conv2 = sext i32 %b to i64
%add = add nsw i64 %conv2, %conv
%add.off = add i64 %add, 2147483648
; CHECK-NOT: llvm.sadd.with.overflow
%0 = icmp ugt i64 %add.off, 4294967295
br i1 %0, label %if.then, label %if.end
if.then:
tail call void @throwAnExceptionOrWhatever() nounwind
br label %if.end
if.end:
ret i64 %add
; CHECK: ret i64
}
; CHECK: @test4
; Should be able to form an i8 sadd computed in an i32.
define zeroext i8 @test4(i8 signext %a, i8 signext %b) nounwind ssp {
entry:
%conv = sext i8 %a to i32
%conv2 = sext i8 %b to i32
%add = add nsw i32 %conv2, %conv
%add4 = add nsw i32 %add, 128
%cmp = icmp ugt i32 %add4, 255
br i1 %cmp, label %if.then, label %if.end
; CHECK: llvm.sadd.with.overflow.i8
if.then: ; preds = %entry
tail call void @throwAnExceptionOrWhatever() nounwind
unreachable
if.end: ; preds = %entry
%conv7 = trunc i32 %add to i8
ret i8 %conv7
; CHECK: ret i8
}
; CHECK: @test5
; CHECK: llvm.uadd.with.overflow
; CHECK: ret i64
define i64 @test5(i64 %a, i64 %b) nounwind ssp {
entry:
%add = add i64 %b, %a
%cmp = icmp ult i64 %add, %a
%Q = select i1 %cmp, i64 %b, i64 42
ret i64 %Q
}
; CHECK: @test6
; CHECK: llvm.uadd.with.overflow
; CHECK: ret i64
define i64 @test6(i64 %a, i64 %b) nounwind ssp {
entry:
%add = add i64 %b, %a
%cmp = icmp ult i64 %add, %b
%Q = select i1 %cmp, i64 %b, i64 42
ret i64 %Q
}
; CHECK: @test7
; CHECK: llvm.uadd.with.overflow
; CHECK: ret i64
define i64 @test7(i64 %a, i64 %b) nounwind ssp {
entry:
%add = add i64 %b, %a
%cmp = icmp ugt i64 %b, %add
%Q = select i1 %cmp, i64 %b, i64 42
ret i64 %Q
}
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