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Differential D141874

[InstCombine] Add tests for reoredering (shift (add (shift x, C0), y), C1); NFC
ClosedPublic

Authored by goldstein.w.n on Jan 16 2023, 3:21 PM.

Details

Reviewers
nikic
majnemer
spatel
Commits
rG8c884655862e: Add tests for reoredering (shift (add (shift x, C0), y), C1); NFC

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Event Timeline

goldstein.w.n created this revision.Jan 16 2023, 3:21 PM
Herald added a project: Restricted Project. · View Herald TranscriptJan 16 2023, 3:21 PM
goldstein.w.n requested review of this revision.Jan 16 2023, 3:21 PM
Herald added a project: Restricted Project. · View Herald TranscriptJan 16 2023, 3:21 PM
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goldstein.w.n retitled this revision from Add tests for reoredering (shift (add (shift x, C0), y), C1); NFC to [InstCombine] Add tests for reoredering (shift (add (shift x, C0), y), C1); NFC.Jan 16 2023, 3:22 PM
goldstein.w.n added reviewers: nikic, majnemer.
Herald added a subscriber: StephenFan. · View Herald TranscriptJan 16 2023, 3:22 PM
goldstein.w.n added a child revision: D141875: [InstCombine] Reorder (shl (add/sub (shl x, C0), y), C1) -> (add/sub (shl x, C0 + C1), (shl y, C1)).Jan 16 2023, 3:22 PM
Harbormaster completed remote builds in B208114: Diff 489641.Jan 16 2023, 4:52 PM
nikic added a reviewer: spatel.Jan 17 2023, 5:31 AM
goldstein.w.n updated this revision to Diff 489875.Jan 17 2023, 10:22 AM

Add tests for sub as well

Harbormaster completed remote builds in B208286: Diff 489875.Jan 17 2023, 11:32 AM
spatel accepted this revision.Jan 27 2023, 11:20 AM

LGTM

llvm/test/Transforms/InstCombine/shift-logic.ll
379

It would be good to add a "negative test" comment to this set of tests (and the corresponding sub variants) in D141875.

That way, it's clear that if they get changed somehow in a subsequent patch, it's probably a miscompile.

This revision is now accepted and ready to land.Jan 27 2023, 11:20 AM
goldstein.w.n updated this revision to Diff 492862.Jan 27 2023, 11:36 AM

Rebase

Harbormaster completed remote builds in B210445: Diff 492862.Jan 27 2023, 1:52 PM
Closed by commit rG8c884655862e: Add tests for reoredering (shift (add (shift x, C0), y), C1); NFC (authored by goldstein.w.n). · Explain WhyJan 27 2023, 3:50 PM
This revision was automatically updated to reflect the committed changes.
goldstein.w.n added a commit: rG8c884655862e: Add tests for reoredering (shift (add (shift x, C0), y), C1); NFC.

Revision Contents

PathSize
llvm/
test/
Transforms/
InstCombine/
182 lines

Diff 492934

llvm/test/Transforms/InstCombine/shift-logic.ll

Show First 20 Lines • Show All 326 Lines • ▼ Show 20 Lines
; CHECK-NEXT: [[TMP2:%.*]] = mul nsw i64 [[TMP0:%.*]], 52 ; CHECK-NEXT: [[TMP2:%.*]] = mul nsw i64 [[TMP0:%.*]], 52
; CHECK-NEXT: [[TMP3:%.*]] = lshr exact i64 [[TMP2]], 2 ; CHECK-NEXT: [[TMP3:%.*]] = lshr exact i64 [[TMP2]], 2
; CHECK-NEXT: ret i64 [[TMP3]] ; CHECK-NEXT: ret i64 [[TMP3]]
; ;
%2 = mul nsw i64 %0, 52 %2 = mul nsw i64 %0, 52
%3 = lshr i64 %2, 2 %3 = lshr i64 %2, 2
ret i64 %3 ret i64 %3
} }
define i8 @shl_add(i8 %x, i8 %y) {
; CHECK-LABEL: @shl_add(
; CHECK-NEXT: [[SH0:%.*]] = shl i8 [[X:%.*]], 3
; CHECK-NEXT: [[R:%.*]] = add i8 [[SH0]], [[Y:%.*]]
; CHECK-NEXT: [[SH1:%.*]] = shl i8 [[R]], 2
; CHECK-NEXT: ret i8 [[SH1]]
;
%sh0 = shl i8 %x, 3
%r = add i8 %sh0, %y
%sh1 = shl i8 %r, 2
ret i8 %sh1
}
define <2 x i8> @shl_add_nonuniform(<2 x i8> %x, <2 x i8> %y) {
; CHECK-LABEL: @shl_add_nonuniform(
; CHECK-NEXT: [[SH0:%.*]] = shl <2 x i8> [[X:%.*]], <i8 3, i8 4>
; CHECK-NEXT: [[R:%.*]] = add <2 x i8> [[SH0]], [[Y:%.*]]
; CHECK-NEXT: [[SH1:%.*]] = shl <2 x i8> [[R]], <i8 2, i8 0>
; CHECK-NEXT: ret <2 x i8> [[SH1]]
;
%sh0 = shl <2 x i8> %x, <i8 3, i8 4>
%r = add <2 x i8> %sh0, %y
%sh1 = shl <2 x i8> %r, <i8 2, i8 0>
ret <2 x i8> %sh1
}
define <2 x i64> @shl_add_undef(<2 x i64> %x, <2 x i64> %py) {
; CHECK-LABEL: @shl_add_undef(
; CHECK-NEXT: [[Y:%.*]] = srem <2 x i64> [[PY:%.*]], <i64 42, i64 42>
; CHECK-NEXT: [[SH0:%.*]] = shl <2 x i64> [[X:%.*]], <i64 5, i64 undef>
; CHECK-NEXT: [[R:%.*]] = add <2 x i64> [[Y]], [[SH0]]
; CHECK-NEXT: [[SH1:%.*]] = shl <2 x i64> [[R]], <i64 7, i64 undef>
; CHECK-NEXT: ret <2 x i64> [[SH1]]
;
%y = srem <2 x i64> %py, <i64 42, i64 42> ; thwart complexity-based canonicalization
%sh0 = shl <2 x i64> %x, <i64 5, i64 undef>
%r = add <2 x i64> %y, %sh0
%sh1 = shl <2 x i64> %r, <i64 7, i64 undef>
ret <2 x i64> %sh1
}
define i8 @lshr_add(i8 %x, i8 %y) {
spatelUnsubmitted
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ReplyInline Actions

It would be good to add a "negative test" comment to this set of tests (and the corresponding sub variants) in D141875.

That way, it's clear that if they get changed somehow in a subsequent patch, it's probably a miscompile.

spatel: It would be good to add a "negative test" comment to this set of tests (and the corresponding…
; CHECK-LABEL: @lshr_add(
; CHECK-NEXT: [[SH0:%.*]] = lshr i8 [[X:%.*]], 3
; CHECK-NEXT: [[R:%.*]] = add i8 [[SH0]], [[Y:%.*]]
; CHECK-NEXT: [[SH1:%.*]] = lshr i8 [[R]], 2
; CHECK-NEXT: ret i8 [[SH1]]
;
%sh0 = lshr i8 %x, 3
%r = add i8 %sh0, %y
%sh1 = lshr i8 %r, 2
ret i8 %sh1
}
define <2 x i8> @lshr_add_nonuniform(<2 x i8> %x, <2 x i8> %y) {
; CHECK-LABEL: @lshr_add_nonuniform(
; CHECK-NEXT: [[SH0:%.*]] = lshr <2 x i8> [[X:%.*]], <i8 3, i8 4>
; CHECK-NEXT: [[R:%.*]] = add <2 x i8> [[SH0]], [[Y:%.*]]
; CHECK-NEXT: [[SH1:%.*]] = lshr <2 x i8> [[R]], <i8 2, i8 0>
; CHECK-NEXT: ret <2 x i8> [[SH1]]
;
%sh0 = lshr <2 x i8> %x, <i8 3, i8 4>
%r = add <2 x i8> %sh0, %y
%sh1 = lshr <2 x i8> %r, <i8 2, i8 0>
ret <2 x i8> %sh1
}
define <2 x i64> @lshr_add_undef(<2 x i64> %x, <2 x i64> %py) {
; CHECK-LABEL: @lshr_add_undef(
; CHECK-NEXT: [[Y:%.*]] = srem <2 x i64> [[PY:%.*]], <i64 42, i64 42>
; CHECK-NEXT: [[SH0:%.*]] = lshr <2 x i64> [[X:%.*]], <i64 5, i64 undef>
; CHECK-NEXT: [[R:%.*]] = add <2 x i64> [[Y]], [[SH0]]
; CHECK-NEXT: [[SH1:%.*]] = lshr <2 x i64> [[R]], <i64 7, i64 undef>
; CHECK-NEXT: ret <2 x i64> [[SH1]]
;
%y = srem <2 x i64> %py, <i64 42, i64 42> ; thwart complexity-based canonicalization
%sh0 = lshr <2 x i64> %x, <i64 5, i64 undef>
%r = add <2 x i64> %y, %sh0
%sh1 = lshr <2 x i64> %r, <i64 7, i64 undef>
ret <2 x i64> %sh1
}
define i8 @shl_sub(i8 %x, i8 %y) {
; CHECK-LABEL: @shl_sub(
; CHECK-NEXT: [[SH0:%.*]] = shl i8 [[X:%.*]], 3
; CHECK-NEXT: [[R:%.*]] = sub i8 [[SH0]], [[Y:%.*]]
; CHECK-NEXT: [[SH1:%.*]] = shl i8 [[R]], 2
; CHECK-NEXT: ret i8 [[SH1]]
;
%sh0 = shl i8 %x, 3
%r = sub i8 %sh0, %y
%sh1 = shl i8 %r, 2
ret i8 %sh1
}
; Make sure we don't commute operands for sub
define i8 @shl_sub_no_commute(i8 %x, i8 %y) {
; CHECK-LABEL: @shl_sub_no_commute(
; CHECK-NEXT: [[SH0:%.*]] = shl i8 [[Y:%.*]], 3
; CHECK-NEXT: [[R:%.*]] = sub i8 [[X:%.*]], [[SH0]]
; CHECK-NEXT: [[SH1:%.*]] = shl i8 [[R]], 2
; CHECK-NEXT: ret i8 [[SH1]]
;
%sh0 = shl i8 %y, 3
%r = sub i8 %x, %sh0
%sh1 = shl i8 %r, 2
ret i8 %sh1
}
define <2 x i8> @shl_sub_nonuniform(<2 x i8> %x, <2 x i8> %y) {
; CHECK-LABEL: @shl_sub_nonuniform(
; CHECK-NEXT: [[SH0:%.*]] = shl <2 x i8> [[X:%.*]], <i8 3, i8 4>
; CHECK-NEXT: [[R:%.*]] = sub <2 x i8> [[SH0]], [[Y:%.*]]
; CHECK-NEXT: [[SH1:%.*]] = shl <2 x i8> [[R]], <i8 2, i8 0>
; CHECK-NEXT: ret <2 x i8> [[SH1]]
;
%sh0 = shl <2 x i8> %x, <i8 3, i8 4>
%r = sub <2 x i8> %sh0, %y
%sh1 = shl <2 x i8> %r, <i8 2, i8 0>
ret <2 x i8> %sh1
}
define <2 x i64> @shl_sub_undef(<2 x i64> %x, <2 x i64> %py) {
; CHECK-LABEL: @shl_sub_undef(
; CHECK-NEXT: [[Y:%.*]] = srem <2 x i64> [[PY:%.*]], <i64 42, i64 42>
; CHECK-NEXT: [[SH0:%.*]] = shl <2 x i64> [[X:%.*]], <i64 5, i64 undef>
; CHECK-NEXT: [[R:%.*]] = sub <2 x i64> [[Y]], [[SH0]]
; CHECK-NEXT: [[SH1:%.*]] = shl <2 x i64> [[R]], <i64 7, i64 undef>
; CHECK-NEXT: ret <2 x i64> [[SH1]]
;
%y = srem <2 x i64> %py, <i64 42, i64 42> ; thwart complexity-based canonicalization
%sh0 = shl <2 x i64> %x, <i64 5, i64 undef>
%r = sub <2 x i64> %y, %sh0
%sh1 = shl <2 x i64> %r, <i64 7, i64 undef>
ret <2 x i64> %sh1
}
define i8 @lshr_sub(i8 %x, i8 %y) {
; CHECK-LABEL: @lshr_sub(
; CHECK-NEXT: [[SH0:%.*]] = lshr i8 [[X:%.*]], 3
; CHECK-NEXT: [[R:%.*]] = sub i8 [[SH0]], [[Y:%.*]]
; CHECK-NEXT: [[SH1:%.*]] = lshr i8 [[R]], 2
; CHECK-NEXT: ret i8 [[SH1]]
;
%sh0 = lshr i8 %x, 3
%r = sub i8 %sh0, %y
%sh1 = lshr i8 %r, 2
ret i8 %sh1
}
define <2 x i8> @lshr_sub_nonuniform(<2 x i8> %x, <2 x i8> %y) {
; CHECK-LABEL: @lshr_sub_nonuniform(
; CHECK-NEXT: [[SH0:%.*]] = lshr <2 x i8> [[X:%.*]], <i8 3, i8 4>
; CHECK-NEXT: [[R:%.*]] = sub <2 x i8> [[SH0]], [[Y:%.*]]
; CHECK-NEXT: [[SH1:%.*]] = lshr <2 x i8> [[R]], <i8 2, i8 0>
; CHECK-NEXT: ret <2 x i8> [[SH1]]
;
%sh0 = lshr <2 x i8> %x, <i8 3, i8 4>
%r = sub <2 x i8> %sh0, %y
%sh1 = lshr <2 x i8> %r, <i8 2, i8 0>
ret <2 x i8> %sh1
}
define <2 x i64> @lshr_sub_undef(<2 x i64> %x, <2 x i64> %py) {
; CHECK-LABEL: @lshr_sub_undef(
; CHECK-NEXT: [[Y:%.*]] = srem <2 x i64> [[PY:%.*]], <i64 42, i64 42>
; CHECK-NEXT: [[SH0:%.*]] = lshr <2 x i64> [[X:%.*]], <i64 5, i64 undef>
; CHECK-NEXT: [[R:%.*]] = sub <2 x i64> [[Y]], [[SH0]]
; CHECK-NEXT: [[SH1:%.*]] = lshr <2 x i64> [[R]], <i64 7, i64 undef>
; CHECK-NEXT: ret <2 x i64> [[SH1]]
;
%y = srem <2 x i64> %py, <i64 42, i64 42> ; thwart complexity-based canonicalization
%sh0 = lshr <2 x i64> %x, <i64 5, i64 undef>
%r = sub <2 x i64> %y, %sh0
%sh1 = lshr <2 x i64> %r, <i64 7, i64 undef>
ret <2 x i64> %sh1
}