extract-highbits-variablemask.ll
2.44 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
; These testcases aren't *identical* but they have the same/similar meaning.
; The obvious case.
define i32 @div(i32 %val, i32 %num) nounwind {
; CHECK-LABEL: 'div'
; CHECK-NEXT: Classifying expressions for: @div
; CHECK-NEXT: %tmp1 = udiv i32 %val, %num
; CHECK-NEXT: --> (%val /u %num) U: full-set S: full-set
; CHECK-NEXT: %tmp2 = mul i32 %tmp1, %num
; CHECK-NEXT: --> ((%val /u %num) * %num) U: full-set S: full-set
; CHECK-NEXT: Determining loop execution counts for: @div
;
%tmp1 = udiv i32 %val, %num
%tmp2 = mul i32 %tmp1, %num
ret i32 %tmp2
}
define i32 @sdiv(i32 %val, i32 %num) nounwind {
; CHECK-LABEL: 'sdiv'
; CHECK-NEXT: Classifying expressions for: @sdiv
; CHECK-NEXT: %tmp1 = sdiv i32 %val, %num
; CHECK-NEXT: --> %tmp1 U: full-set S: full-set
; CHECK-NEXT: %tmp2 = mul i32 %tmp1, %num
; CHECK-NEXT: --> (%num * %tmp1) U: full-set S: full-set
; CHECK-NEXT: Determining loop execution counts for: @sdiv
;
%tmp1 = sdiv i32 %val, %num
%tmp2 = mul i32 %tmp1, %num
ret i32 %tmp2
}
; Or, it could be a number of equivalent patterns with mask:
; b) x & (-1 << nbits)
; d) x >> (32 - y) << (32 - y)
define i32 @mask_b(i32 %val, i32 %numlowbits) nounwind {
; CHECK-LABEL: 'mask_b'
; CHECK-NEXT: Classifying expressions for: @mask_b
; CHECK-NEXT: %mask = shl i32 -1, %numlowbits
; CHECK-NEXT: --> %mask U: full-set S: full-set
; CHECK-NEXT: %masked = and i32 %mask, %val
; CHECK-NEXT: --> %masked U: full-set S: full-set
; CHECK-NEXT: Determining loop execution counts for: @mask_b
;
%mask = shl i32 -1, %numlowbits
%masked = and i32 %mask, %val
ret i32 %masked
}
define i32 @mask_d(i32 %val, i32 %lowbits) nounwind {
; CHECK-LABEL: 'mask_d'
; CHECK-NEXT: Classifying expressions for: @mask_d
; CHECK-NEXT: %numlowbits = sub i32 32, %lowbits
; CHECK-NEXT: --> (32 + (-1 * %lowbits)) U: full-set S: full-set
; CHECK-NEXT: %lowbitscleared = lshr i32 %val, %numlowbits
; CHECK-NEXT: --> %lowbitscleared U: full-set S: full-set
; CHECK-NEXT: %masked = shl i32 %lowbitscleared, %numlowbits
; CHECK-NEXT: --> %masked U: full-set S: full-set
; CHECK-NEXT: Determining loop execution counts for: @mask_d
;
%numlowbits = sub i32 32, %lowbits
%lowbitscleared = lshr i32 %val, %numlowbits
%masked = shl i32 %lowbitscleared, %numlowbits
ret i32 %masked
}