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Differential D152672

[InstCombine] Add tests for canonicalizing `(X^(X-1)) u{ge,lt} X` as pow2 test; NFC
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Authored by goldstein.w.n on Jun 11 2023, 11:28 PM.

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nikic
spatel
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rGf21a042a8ceb: [InstCombine] Add tests for canonicalizing `(X^(X-1)) u{ge,lt} X` as pow2 test…

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goldstein.w.n created this revision.Jun 11 2023, 11:28 PM
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goldstein.w.n requested review of this revision.Jun 11 2023, 11:28 PM
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goldstein.w.n added a child revision: D152673: [InstCombine] Canonicalize `(X^(X-1)) u{ge,lt} X` as pow2 test.Jun 11 2023, 11:31 PM
Harbormaster completed remote builds in B238104: Diff 530395.Jun 12 2023, 12:14 AM
goldstein.w.n updated this revision to Diff 530577.Jun 12 2023, 10:23 AM

Rebase

goldstein.w.n added a parent revision: D152728: [InstCombine] Factor out power of 2 comparison patterns to helper; NFC.Jun 12 2023, 10:23 AM
nikic accepted this revision.Jun 12 2023, 11:59 AM

LGTM

llvm/test/Transforms/InstCombine/ispow2.ll
1213

I'd add two more negative tests where the operands in and/xor and xor/icmp are not the same.

This revision is now accepted and ready to land.Jun 12 2023, 11:59 AM
Harbormaster completed remote builds in B238240: Diff 530577.Jun 12 2023, 12:27 PM
goldstein.w.n updated this revision to Diff 530733.Jun 12 2023, 5:52 PM

Add more negative tests

Harbormaster completed remote builds in B238359: Diff 530733.Jun 12 2023, 7:31 PM
goldstein.w.n updated this revision to Diff 535076.Jun 27 2023, 11:31 AM

Rebase

Harbormaster completed remote builds in B241556: Diff 535076.Jun 27 2023, 2:02 PM
goldstein.w.n updated this revision to Diff 541142.Jul 17 2023, 11:00 AM

Rebase

goldstein.w.n updated this revision to Diff 541210.Jul 17 2023, 1:28 PM

Rebase

Harbormaster completed remote builds in B245985: Diff 541210.Jul 17 2023, 6:58 PM
goldstein.w.n updated this revision to Diff 541582.Jul 18 2023, 8:52 AM

Rebase

Harbormaster completed remote builds in B246261: Diff 541582.Jul 18 2023, 3:37 PM
This revision was landed with ongoing or failed builds.Jul 21 2023, 12:15 PM
Closed by commit rGf21a042a8ceb: [InstCombine] Add tests for canonicalizing `(X^(X-1)) u{ge,lt} X` as pow2 test… (authored by goldstein.w.n). · Explain Why
This revision was automatically updated to reflect the committed changes.
goldstein.w.n added a commit: rGf21a042a8ceb: [InstCombine] Add tests for canonicalizing `(X^(X-1)) u{ge,lt} X` as pow2 test….

Revision Contents

PathSize
llvm/
test/
Transforms/
InstCombine/
115 lines

Diff 543021

llvm/test/Transforms/InstCombine/ispow2.ll

Show First 20 Lines • Show All 1,147 Lines • ▼ Show 20 Lines
; CHECK-NEXT: [[R:%.*]] = icmp sge i32 [[X_AND_NX]], [[X]] ; CHECK-NEXT: [[R:%.*]] = icmp sge i32 [[X_AND_NX]], [[X]]
; CHECK-NEXT: ret i1 [[R]] ; CHECK-NEXT: ret i1 [[R]]
; ;
%nx = sub i32 0, %x %nx = sub i32 0, %x
%x_and_nx = and i32 %x, %nx %x_and_nx = and i32 %x, %nx
%r = icmp sge i32 %x_and_nx, %x %r = icmp sge i32 %x_and_nx, %x
ret i1 %r ret i1 %r
} }
define i1 @blsmsk_is_p2_or_z(i32 %xx, i32 %yy) {
; CHECK-LABEL: @blsmsk_is_p2_or_z(
; CHECK-NEXT: [[X:%.*]] = or i32 [[XX:%.*]], [[YY:%.*]]
; CHECK-NEXT: [[XM1:%.*]] = add i32 [[X]], -1
; CHECK-NEXT: [[Y:%.*]] = xor i32 [[X]], [[XM1]]
; CHECK-NEXT: [[R:%.*]] = icmp uge i32 [[X]], [[Y]]
; CHECK-NEXT: ret i1 [[R]]
;
%x = or i32 %xx, %yy
%xm1 = add i32 %x, -1
%y = xor i32 %x, %xm1
%r = icmp uge i32 %x, %y
ret i1 %r
}
define i1 @blsmsk_isnt_p2_or_z(i32 %x) {
; CHECK-LABEL: @blsmsk_isnt_p2_or_z(
; CHECK-NEXT: [[XM1:%.*]] = add i32 [[X:%.*]], -1
; CHECK-NEXT: [[Y:%.*]] = xor i32 [[XM1]], [[X]]
; CHECK-NEXT: [[R:%.*]] = icmp ult i32 [[Y]], [[X]]
; CHECK-NEXT: ret i1 [[R]]
;
%xm1 = add i32 %x, -1
%y = xor i32 %x, %xm1
%r = icmp ult i32 %y, %x
ret i1 %r
}
define i1 @blsmsk_is_p2_or_z_fail(i32 %xx, i32 %yy) {
; CHECK-LABEL: @blsmsk_is_p2_or_z_fail(
; CHECK-NEXT: [[X:%.*]] = or i32 [[XX:%.*]], [[YY:%.*]]
; CHECK-NEXT: [[XM1:%.*]] = add i32 [[X]], -1
; CHECK-NEXT: [[Y:%.*]] = xor i32 [[X]], [[XM1]]
; CHECK-NEXT: [[R:%.*]] = icmp ugt i32 [[X]], [[Y]]
; CHECK-NEXT: ret i1 [[R]]
;
%x = or i32 %xx, %yy
%xm1 = add i32 %x, -1
%y = xor i32 %x, %xm1
%r = icmp ugt i32 %x, %y
ret i1 %r
}
define i1 @blsmsk_isnt_p2_or_z_fail(i32 %x) {
; CHECK-LABEL: @blsmsk_isnt_p2_or_z_fail(
; CHECK-NEXT: [[XM1:%.*]] = add i32 [[X:%.*]], -1
; CHECK-NEXT: [[Y:%.*]] = xor i32 [[XM1]], [[X]]
; CHECK-NEXT: [[R:%.*]] = icmp ule i32 [[Y]], [[X]]
; CHECK-NEXT: ret i1 [[R]]
;
%xm1 = add i32 %x, -1
%y = xor i32 %x, %xm1
%r = icmp ule i32 %y, %x
ret i1 %r
}
declare void @use.i32(i32)
nikicUnsubmitted
Not Done
ReplyInline Actions

I'd add two more negative tests where the operands in and/xor and xor/icmp are not the same.

nikic: I'd add two more negative tests where the operands in and/xor and xor/icmp are not the same.
define i1 @blsmsk_isnt_p2_or_z_fail_multiuse(i32 %x) {
; CHECK-LABEL: @blsmsk_isnt_p2_or_z_fail_multiuse(
; CHECK-NEXT: [[XM1:%.*]] = add i32 [[X:%.*]], -1
; CHECK-NEXT: [[Y:%.*]] = xor i32 [[XM1]], [[X]]
; CHECK-NEXT: call void @use.i32(i32 [[Y]])
; CHECK-NEXT: [[R:%.*]] = icmp ult i32 [[Y]], [[X]]
; CHECK-NEXT: ret i1 [[R]]
;
%xm1 = add i32 %x, -1
%y = xor i32 %x, %xm1
call void @use.i32(i32 %y)
%r = icmp ult i32 %y, %x
ret i1 %r
}
define i1 @blsmsk_isnt_p2_or_z_fail_wrong_add(i32 %x, i32 %z) {
; CHECK-LABEL: @blsmsk_isnt_p2_or_z_fail_wrong_add(
; CHECK-NEXT: [[XM1:%.*]] = add i32 [[Z:%.*]], -1
; CHECK-NEXT: [[Y:%.*]] = xor i32 [[XM1]], [[X:%.*]]
; CHECK-NEXT: [[R:%.*]] = icmp ult i32 [[Y]], [[X]]
; CHECK-NEXT: ret i1 [[R]]
;
%xm1 = add i32 %z, -1
%y = xor i32 %x, %xm1
%r = icmp ult i32 %y, %x
ret i1 %r
}
define i1 @blsmsk_isnt_p2_or_z_fail_bad_xor(i32 %x, i32 %z) {
; CHECK-LABEL: @blsmsk_isnt_p2_or_z_fail_bad_xor(
; CHECK-NEXT: [[XM1:%.*]] = add i32 [[X:%.*]], -1
; CHECK-NEXT: [[Y:%.*]] = xor i32 [[XM1]], [[Z:%.*]]
; CHECK-NEXT: [[R:%.*]] = icmp ult i32 [[Y]], [[X]]
; CHECK-NEXT: ret i1 [[R]]
;
%xm1 = add i32 %x, -1
%y = xor i32 %z, %xm1
%r = icmp ult i32 %y, %x
ret i1 %r
}
define i1 @blsmsk_is_p2_or_z_fail_bad_cmp(i32 %x, i32 %z) {
; CHECK-LABEL: @blsmsk_is_p2_or_z_fail_bad_cmp(
; CHECK-NEXT: [[XM1:%.*]] = add i32 [[X:%.*]], -1
; CHECK-NEXT: [[Y:%.*]] = xor i32 [[XM1]], [[X]]
; CHECK-NEXT: [[R:%.*]] = icmp uge i32 [[Y]], [[Z:%.*]]
; CHECK-NEXT: ret i1 [[R]]
;
%xm1 = add i32 %x, -1
%y = xor i32 %x, %xm1
%r = icmp uge i32 %y, %z
ret i1 %r
}