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; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py
; RUN: opt -S -analyze -scalar-evolution < %s | FileCheck %s
; The obvious case.
define i32 @mul(i32 %val) nounwind {
; CHECK-LABEL: 'mul'
; CHECK-NEXT: Classifying expressions for: @mul
; CHECK-NEXT: %tmp1 = mul i32 %val, 16
; CHECK-NEXT: --> (16 * %val) U: [0,-15) S: [-2147483648,2147483633)
; CHECK-NEXT: %tmp2 = udiv i32 %tmp1, 16
; CHECK-NEXT: --> ((16 * %val) /u 16) U: [0,268435456) S: [0,268435456)
; CHECK-NEXT: Determining loop execution counts for: @mul
;
%tmp1 = mul i32 %val, 16
%tmp2 = udiv i32 %tmp1, 16
ret i32 %tmp2
}
; Or, it could be any number of equivalent patterns with mask:
; a) x & (1 << nbits) - 1
; b) x & ~(-1 << nbits)
; c) x & (-1 >> (32 - y))
; d) x << (32 - y) >> (32 - y)
define i32 @mask_abc(i32 %val) nounwind {
; CHECK-LABEL: 'mask_abc'
; CHECK-NEXT: Classifying expressions for: @mask_abc
; CHECK-NEXT: %masked = and i32 %val, 15
; CHECK-NEXT: --> (zext i4 (trunc i32 %val to i4) to i32) U: [0,16) S: [0,16)
; CHECK-NEXT: Determining loop execution counts for: @mask_abc
;
%masked = and i32 %val, 15
ret i32 %masked
}
define i32 @mask_d(i32 %val) nounwind {
; CHECK-LABEL: 'mask_d'
; CHECK-NEXT: Classifying expressions for: @mask_d
; CHECK-NEXT: %highbitscleared = shl i32 %val, 4
; CHECK-NEXT: --> (16 * %val) U: [0,-15) S: [-2147483648,2147483633)
; CHECK-NEXT: %masked = lshr i32 %highbitscleared, 4
; CHECK-NEXT: --> ((16 * %val) /u 16) U: [0,268435456) S: [0,268435456)
; CHECK-NEXT: Determining loop execution counts for: @mask_d
;
%highbitscleared = shl i32 %val, 4
%masked = lshr i32 %highbitscleared, 4
ret i32 %masked
}
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