File: extract-highbits-variablemask.ll

package info (click to toggle)
llvm-toolchain-11 1%3A11.0.1-2
  • links: PTS, VCS
  • area: main
  • in suites: bullseye
  • size: 995,808 kB
  • sloc: cpp: 4,767,656; ansic: 760,916; asm: 477,436; python: 170,940; objc: 69,804; lisp: 29,914; sh: 23,855; f90: 18,173; pascal: 7,551; perl: 7,471; ml: 5,603; awk: 3,489; makefile: 2,573; xml: 915; cs: 573; fortran: 503; javascript: 452
file content (68 lines) | stat: -rw-r--r-- 2,501 bytes parent folder | download | duplicates (7)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
; 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
}