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@chfast
Last active August 29, 2015 14:16
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LLVM shift test
; RUN: opt < %s -constprop -S | FileCheck %s
; CHECK-LABEL: shift_undef_65
define void @shift_undef_65(i65* %p) {
%r1 = lshr i65 2, 18446744073709551617
; CHECK: store i65 undef, %p
store i65 %r1, i65* %p
%r2 = ashr i65 4, 18446744073709551617
; CHECK: store i65 undef, %p
store i65 %r2, i65* %p
%r3 = shl i65 1, 18446744073709551617
; CHECK: store i65 undef, %p
store i65 %r3, i65* %p
ret void
}
; CHECK-LABEL: shift_undef_256
define void @shift_undef_256(i256* %p) {
%r1 = lshr i256 2, 18446744073709551617
; CHECK: store i256 undef, %p
store i256 %r1, i256* %p
%r2 = ashr i256 4, 18446744073709551618
; CHECK: store i256 undef, %p
store i256 %r2, i256* %p
%r3 = shl i256 1, 18446744073709551619
; CHECK: store i256 undef, %p
store i256 %r3, i256* %p
ret void
}
; CHECK-LABEL: shift_undef_511
define void @shift_undef_511(i511* %p) {
%r1 = lshr i511 -1, 1208925819614629174706276 ; 2^80 + 100
; CHECK: store i511 undef, %p
store i511 %r1, i511* %p
%r2 = ashr i511 -2, 1208925819614629174706200
; CHECK: store i511 undef, %p
store i511 %r2, i511* %p
%r3 = shl i511 -3, 1208925819614629174706180
; CHECK: store i511 undef, %p
store i511 %r3, i511* %p
ret void
}
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