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; RUN: opt < %s -disable-output "-passes=print<scalar-evolution>" 2>&1 | FileCheck %s
; Check that we convert
; trunc(C * a) -> trunc(C) * trunc(a)
; if C is a constant.
; CHECK-LABEL: @trunc_of_mul
define i8 @trunc_of_mul(i32 %a) {
%b = mul i32 %a, 100
; CHECK: %c
; CHECK-NEXT: --> (100 * (trunc i32 %a to i8))
%c = trunc i32 %b to i8
ret i8 %c
}
; Check that we convert
; trunc(C + a) -> trunc(C) + trunc(a)
; if C is a constant.
; CHECK-LABEL: @trunc_of_add
define i8 @trunc_of_add(i32 %a) {
%b = add i32 %a, 100
; CHECK: %c
; CHECK-NEXT: --> (100 + (trunc i32 %a to i8))
%c = trunc i32 %b to i8
ret i8 %c
}
; Check that we truncate to zero values assumed to have at least as many
; trailing zeros as the target type.
; CHECK-LABEL: @trunc_to_assumed_zeros
define i8 @trunc_to_assumed_zeros(i32* %p) {
%a = load i32, i32* %p
%and = and i32 %a, 255
%cmp = icmp eq i32 %and, 0
tail call void @llvm.assume(i1 %cmp)
; CHECK: %c
; CHECK-NEXT: --> 0
%c = trunc i32 %a to i8
; CHECK: %d
; CHECK-NEXT: --> false
%d = trunc i32 %a to i1
; CHECK: %e
; CHECK-NEXT: --> (trunc i32 %a to i16)
%e = trunc i32 %a to i16
ret i8 %c
}
declare void @llvm.assume(i1 noundef) nofree nosync nounwind willreturn
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