Skip to content

[GlobalISel] Fold bitcast(undef) to undef. #111491

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Oct 9, 2024
Merged

[GlobalISel] Fold bitcast(undef) to undef. #111491

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 1 addition & 1 deletion llvm/include/llvm/Target/GlobalISel/Combine.td
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -420,7 +420,7 @@ def unary_undef_to_zero: GICombineRule<
// replaced with undef.
def propagate_undef_any_op: GICombineRule<
(defs root:$root),
(match (wip_match_opcode G_ADD, G_FPTOSI, G_FPTOUI, G_SUB, G_XOR, G_TRUNC):$root,
(match (wip_match_opcode G_ADD, G_FPTOSI, G_FPTOUI, G_SUB, G_XOR, G_TRUNC, G_BITCAST):$root,
[{ return Helper.matchAnyExplicitUseIsUndef(*${root}); }]),
(apply [{ Helper.replaceInstWithUndef(*${root}); }])>;

Expand Down
19 changes: 4 additions & 15 deletions llvm/test/CodeGen/AArch64/concat-vector.ll
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -189,28 +189,17 @@ define <8 x i16> @concat_v8s16_v2s16(ptr %ptr) {
; CHECK-GI-NEXT: xtn v0.4h, v0.4s
; CHECK-GI-NEXT: fmov w8, s0
; CHECK-GI-NEXT: mov v0.s[0], w8
; CHECK-GI-NEXT: mov v0.s[1], w8
; CHECK-GI-NEXT: mov v0.s[2], w8
; CHECK-GI-NEXT: mov v0.s[3], w8
; CHECK-GI-NEXT: ret
%a = load <2 x i16>, ptr %ptr
%b = shufflevector <2 x i16> %a, <2 x i16> %a, <8 x i32> <i32 0, i32 1, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef>
ret <8 x i16> %b
}

define <16 x i8> @concat_v16s8_v4s8(ptr %ptr) {
; CHECK-SD-LABEL: concat_v16s8_v4s8:
; CHECK-SD: // %bb.0:
; CHECK-SD-NEXT: ldr s0, [x0]
; CHECK-SD-NEXT: ret
;
; CHECK-GI-LABEL: concat_v16s8_v4s8:
; CHECK-GI: // %bb.0:
; CHECK-GI-NEXT: ldr s0, [x0]
; CHECK-GI-NEXT: mov v0.s[1], w8
; CHECK-GI-NEXT: mov v0.s[2], w8
; CHECK-GI-NEXT: mov v0.s[3], w8
; CHECK-GI-NEXT: ret
; CHECK-LABEL: concat_v16s8_v4s8:
; CHECK: // %bb.0:
; CHECK-NEXT: ldr s0, [x0]
; CHECK-NEXT: ret
%a = load <4 x i8>, ptr %ptr
%b = shufflevector <4 x i8> %a, <4 x i8> %a, <16 x i32> <i32 0, i32 1, i32 2, i32 3, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef>
ret <16 x i8> %b
Expand Down
Loading