extract-highbits-sameconstmask.ll
2.09 KB
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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 @div(i32 %val) nounwind {
; CHECK-LABEL: 'div'
; CHECK-NEXT: Classifying expressions for: @div
; CHECK-NEXT: %tmp1 = udiv i32 %val, 16
; CHECK-NEXT: --> (%val /u 16) U: [0,268435456) S: [0,268435456)
; CHECK-NEXT: %tmp2 = mul i32 %tmp1, 16
; CHECK-NEXT: --> (16 * (%val /u 16))<nuw> U: [0,-15) S: [-2147483648,2147483633)
; CHECK-NEXT: Determining loop execution counts for: @div
;
%tmp1 = udiv i32 %val, 16
%tmp2 = mul i32 %tmp1, 16
ret i32 %tmp2
}
define i32 @sdiv(i32 %val) nounwind {
; CHECK-LABEL: 'sdiv'
; CHECK-NEXT: Classifying expressions for: @sdiv
; CHECK-NEXT: %tmp1 = sdiv i32 %val, 16
; CHECK-NEXT: --> %tmp1 U: full-set S: [-134217728,134217728)
; CHECK-NEXT: %tmp2 = mul i32 %tmp1, 16
; CHECK-NEXT: --> (16 * %tmp1)<nsw> U: [0,-15) S: [-2147483648,2147483633)
; CHECK-NEXT: Determining loop execution counts for: @sdiv
;
%tmp1 = sdiv i32 %val, 16
%tmp2 = mul i32 %tmp1, 16
ret i32 %tmp2
}
; Or, it could be a number of equivalent patterns with mask:
; b) x & (-1 << nbits)
; d) x >> nbits << nbits
define i32 @mask_b(i32 %val) nounwind {
; CHECK-LABEL: 'mask_b'
; CHECK-NEXT: Classifying expressions for: @mask_b
; CHECK-NEXT: %masked = and i32 %val, -16
; CHECK-NEXT: --> (16 * (%val /u 16))<nuw> U: [0,-15) S: [-2147483648,2147483633)
; CHECK-NEXT: Determining loop execution counts for: @mask_b
;
%masked = and i32 %val, -16
ret i32 %masked
}
define i32 @mask_d(i32 %val) nounwind {
; CHECK-LABEL: 'mask_d'
; CHECK-NEXT: Classifying expressions for: @mask_d
; CHECK-NEXT: %lowbitscleared = lshr i32 %val, 4
; CHECK-NEXT: --> (%val /u 16) U: [0,268435456) S: [0,268435456)
; CHECK-NEXT: %masked = shl i32 %lowbitscleared, 4
; CHECK-NEXT: --> (16 * (%val /u 16))<nuw> U: [0,-15) S: [-2147483648,2147483633)
; CHECK-NEXT: Determining loop execution counts for: @mask_d
;
%lowbitscleared = lshr i32 %val, 4
%masked = shl i32 %lowbitscleared, 4
ret i32 %masked
}