This is an archive of the discontinued LLVM Phabricator instance.

Differential D145335

[InstSimplify] Add tests for `(shl nuw nsw X, BitWidth - 1)` -> `0`; NFC
ClosedPublic

Authored by goldstein.w.n on Mar 5 2023, 2:45 PM.

Details

Reviewers
nikic
spatel
majnemer
Commits
rGa1771ad1d512: [InstSimplify] Add tests for `(shl nuw nsw X, BitWidth - 1)` -> `0`; NFC

Diff Detail

Event Timeline

goldstein.w.n created this revision.Mar 5 2023, 2:45 PM
Herald added a project: Restricted Project. · View Herald TranscriptMar 5 2023, 2:45 PM
goldstein.w.n requested review of this revision.Mar 5 2023, 2:45 PM
Herald added a project: Restricted Project. · View Herald TranscriptMar 5 2023, 2:45 PM
Herald added a subscriber: llvm-commits. · View Herald Transcript
goldstein.w.n added reviewers: nikic, spatel, majnemer.Mar 5 2023, 2:46 PM
Herald added a subscriber: StephenFan. · View Herald TranscriptMar 5 2023, 2:46 PM
goldstein.w.n added a child revision: D145327: [InstSimplify] Simplify `(shl nsw nuw X, BitWidth - 1)` -> `0`.Mar 5 2023, 2:46 PM
Harbormaster completed remote builds in B217461: Diff 502480.Mar 5 2023, 3:35 PM
Mztea928 added a child revision: D145351: [cmake] Export component info needed to determine which libraries are in libLLVM.so..Mar 5 2023, 10:16 PM
nikic accepted this revision.Mar 6 2023, 1:43 AM

LG

llvm/test/Transforms/InstSimplify/shift.ll
364

we are match -> we match the?

This revision is now accepted and ready to land.Mar 6 2023, 1:43 AM
goldstein.w.n removed a child revision: D145351: [cmake] Export component info needed to determine which libraries are in libLLVM.so..Mar 6 2023, 10:24 AM
goldstein.w.n updated this revision to Diff 502701.Mar 6 2023, 10:27 AM

Rebase

goldstein.w.n marked an inline comment as done.Mar 6 2023, 10:34 AM
goldstein.w.n updated this revision to Diff 502711.Mar 6 2023, 10:34 AM

Fix grammars

Harbormaster completed remote builds in B217631: Diff 502711.Mar 6 2023, 2:22 PM
This revision was landed with ongoing or failed builds.Mar 6 2023, 6:31 PM
Closed by commit rGa1771ad1d512: [InstSimplify] Add tests for `(shl nuw nsw X, BitWidth - 1)` -> `0`; NFC (authored by goldstein.w.n). · Explain Why
This revision was automatically updated to reflect the committed changes.
goldstein.w.n added a commit: rGa1771ad1d512: [InstSimplify] Add tests for `(shl nuw nsw X, BitWidth - 1)` -> `0`; NFC.

Revision Contents

PathSize
llvm/
test/
Transforms/
InstSimplify/
50 lines

Diff 502888

llvm/test/Transforms/InstSimplify/shift.ll

Show First 20 Lines • Show All 344 Lines • ▼ Show 20 Lines
define <vscale x 4 x i16> @lshr_scalable_overshift(<vscale x 4 x i16> %va) { define <vscale x 4 x i16> @lshr_scalable_overshift(<vscale x 4 x i16> %va) {
; CHECK-LABEL: @lshr_scalable_overshift( ; CHECK-LABEL: @lshr_scalable_overshift(
; CHECK-NEXT: ret <vscale x 4 x i16> poison ; CHECK-NEXT: ret <vscale x 4 x i16> poison
; ;
%vc = lshr <vscale x 4 x i16> %va, shufflevector (<vscale x 4 x i16> insertelement (<vscale x 4 x i16> poison, i16 16, i32 0), <vscale x 4 x i16> poison, <vscale x 4 x i32> zeroinitializer) %vc = lshr <vscale x 4 x i16> %va, shufflevector (<vscale x 4 x i16> insertelement (<vscale x 4 x i16> poison, i16 16, i32 0), <vscale x 4 x i16> poison, <vscale x 4 x i32> zeroinitializer)
ret <vscale x 4 x i16> %vc ret <vscale x 4 x i16> %vc
} }
; shl nsw+nuw is 0
define i8 @shl_nsw_nuw_7_eq_0(i8 %x) {
; CHECK-LABEL: @shl_nsw_nuw_7_eq_0(
; CHECK-NEXT: [[Y:%.*]] = shl nuw nsw i8 [[X:%.*]], 7
; CHECK-NEXT: ret i8 [[Y]]
;
%y = shl nsw nuw i8 %x, 7
ret i8 %y
}
; Make sure we match the element width
nikicUnsubmitted
Done
ReplyInline Actions

we are match -> we match the?

nikic: we are match -> we match the?
define <2 x i8> @shl_vec_nsw_nuw_7_eq_0(<2 x i8> %x) {
; CHECK-LABEL: @shl_vec_nsw_nuw_7_eq_0(
; CHECK-NEXT: [[Y:%.*]] = shl nuw nsw <2 x i8> [[X:%.*]], <i8 7, i8 7>
; CHECK-NEXT: ret <2 x i8> [[Y]]
;
%y = shl nsw nuw <2 x i8> %x, <i8 7, i8 7>
ret <2 x i8> %y
}
; negative test (missing nuw)
define i8 @shl_nsw_7_fail_missing_nuw(i8 %x) {
; CHECK-LABEL: @shl_nsw_7_fail_missing_nuw(
; CHECK-NEXT: [[Y:%.*]] = shl nsw i8 [[X:%.*]], 7
; CHECK-NEXT: ret i8 [[Y]]
;
%y = shl nsw i8 %x, 7
ret i8 %y
}
; negative test (missing nsw)
define i8 @shl_nuw_7_fail_missing_nsw(i8 %x) {
; CHECK-LABEL: @shl_nuw_7_fail_missing_nsw(
; CHECK-NEXT: [[Y:%.*]] = shl nuw i8 [[X:%.*]], 7
; CHECK-NEXT: ret i8 [[Y]]
;
%y = shl nuw i8 %x, 7
ret i8 %y
}
; negative test (shift value != bitwdth - 1)
define i8 @shl_nsw_nuw_6_do_nothing(i8 %x) {
; CHECK-LABEL: @shl_nsw_nuw_6_do_nothing(
; CHECK-NEXT: [[Y:%.*]] = shl nuw nsw i8 [[X:%.*]], 6
; CHECK-NEXT: ret i8 [[Y]]
;
%y = shl nsw nuw i8 %x, 6
ret i8 %y
}