| ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py |
| ; RUN: opt < %s -instcombine -S | FileCheck %s |
| |
| ; Narrow the select operands to eliminate the existing shuffles and replace a wide select with a narrow select. |
| |
| define <2 x i8> @narrow_shuffle_of_select(<2 x i1> %cmp, <4 x i8> %x, <4 x i8> %y) { |
| ; CHECK-LABEL: @narrow_shuffle_of_select( |
| ; CHECK-NEXT: [[TMP1:%.*]] = shufflevector <4 x i8> [[X:%.*]], <4 x i8> poison, <2 x i32> <i32 0, i32 1> |
| ; CHECK-NEXT: [[TMP2:%.*]] = shufflevector <4 x i8> [[Y:%.*]], <4 x i8> poison, <2 x i32> <i32 0, i32 1> |
| ; CHECK-NEXT: [[R:%.*]] = select <2 x i1> [[CMP:%.*]], <2 x i8> [[TMP1]], <2 x i8> [[TMP2]] |
| ; CHECK-NEXT: ret <2 x i8> [[R]] |
| ; |
| %widecmp = shufflevector <2 x i1> %cmp, <2 x i1> undef, <4 x i32> <i32 0, i32 1, i32 undef, i32 undef> |
| %widesel = select <4 x i1> %widecmp, <4 x i8> %x, <4 x i8> %y |
| %r = shufflevector <4 x i8> %widesel, <4 x i8> undef, <2 x i32> <i32 0, i32 1> |
| ret <2 x i8> %r |
| } |
| |
| ; The 1st shuffle is not extending with undefs, but demanded elements corrects that. |
| |
| define <2 x i8> @narrow_shuffle_of_select_overspecified_extend(<2 x i1> %cmp, <4 x i8> %x, <4 x i8> %y) { |
| ; CHECK-LABEL: @narrow_shuffle_of_select_overspecified_extend( |
| ; CHECK-NEXT: [[TMP1:%.*]] = shufflevector <4 x i8> [[X:%.*]], <4 x i8> poison, <2 x i32> <i32 0, i32 1> |
| ; CHECK-NEXT: [[TMP2:%.*]] = shufflevector <4 x i8> [[Y:%.*]], <4 x i8> poison, <2 x i32> <i32 0, i32 1> |
| ; CHECK-NEXT: [[R:%.*]] = select <2 x i1> [[CMP:%.*]], <2 x i8> [[TMP1]], <2 x i8> [[TMP2]] |
| ; CHECK-NEXT: ret <2 x i8> [[R]] |
| ; |
| %widecmp = shufflevector <2 x i1> %cmp, <2 x i1> undef, <4 x i32> <i32 0, i32 1, i32 0, i32 1> |
| %widesel = select <4 x i1> %widecmp, <4 x i8> %x, <4 x i8> %y |
| %r = shufflevector <4 x i8> %widesel, <4 x i8> undef, <2 x i32> <i32 0, i32 1> |
| ret <2 x i8> %r |
| } |
| |
| ; Verify that undef elements are acceptable for identity shuffle mask. Also check FP types. |
| |
| define <3 x float> @narrow_shuffle_of_select_undefs(<3 x i1> %cmp, <4 x float> %x, <4 x float> %y) { |
| ; CHECK-LABEL: @narrow_shuffle_of_select_undefs( |
| ; CHECK-NEXT: [[TMP1:%.*]] = shufflevector <4 x float> [[X:%.*]], <4 x float> poison, <3 x i32> <i32 0, i32 1, i32 undef> |
| ; CHECK-NEXT: [[TMP2:%.*]] = shufflevector <4 x float> [[Y:%.*]], <4 x float> poison, <3 x i32> <i32 0, i32 1, i32 undef> |
| ; CHECK-NEXT: [[R:%.*]] = select <3 x i1> [[CMP:%.*]], <3 x float> [[TMP1]], <3 x float> [[TMP2]] |
| ; CHECK-NEXT: ret <3 x float> [[R]] |
| ; |
| %widecmp = shufflevector <3 x i1> %cmp, <3 x i1> undef, <4 x i32> <i32 undef, i32 1, i32 2, i32 undef> |
| %widesel = select <4 x i1> %widecmp, <4 x float> %x, <4 x float> %y |
| %r = shufflevector <4 x float> %widesel, <4 x float> undef, <3 x i32> <i32 0, i32 1, i32 undef> |
| ret <3 x float> %r |
| } |
| |
| declare void @use(<4 x i8>) |
| declare void @use_cmp(<4 x i1>) |
| |
| ; Negative test - extra use would require more instructions than we started with. |
| |
| define <2 x i8> @narrow_shuffle_of_select_use1(<2 x i1> %cmp, <4 x i8> %x, <4 x i8> %y) { |
| ; CHECK-LABEL: @narrow_shuffle_of_select_use1( |
| ; CHECK-NEXT: [[WIDECMP:%.*]] = shufflevector <2 x i1> [[CMP:%.*]], <2 x i1> undef, <4 x i32> <i32 0, i32 1, i32 undef, i32 undef> |
| ; CHECK-NEXT: [[WIDESEL:%.*]] = select <4 x i1> [[WIDECMP]], <4 x i8> [[X:%.*]], <4 x i8> [[Y:%.*]] |
| ; CHECK-NEXT: call void @use(<4 x i8> [[WIDESEL]]) |
| ; CHECK-NEXT: [[R:%.*]] = shufflevector <4 x i8> [[WIDESEL]], <4 x i8> undef, <2 x i32> <i32 0, i32 1> |
| ; CHECK-NEXT: ret <2 x i8> [[R]] |
| ; |
| %widecmp = shufflevector <2 x i1> %cmp, <2 x i1> undef, <4 x i32> <i32 0, i32 1, i32 undef, i32 undef> |
| %widesel = select <4 x i1> %widecmp, <4 x i8> %x, <4 x i8> %y |
| call void @use(<4 x i8> %widesel) |
| %r = shufflevector <4 x i8> %widesel, <4 x i8> undef, <2 x i32> <i32 0, i32 1> |
| ret <2 x i8> %r |
| } |
| |
| ; Negative test - extra use would require more instructions than we started with. |
| |
| define <2 x i8> @narrow_shuffle_of_select_use2(<2 x i1> %cmp, <4 x i8> %x, <4 x i8> %y) { |
| ; CHECK-LABEL: @narrow_shuffle_of_select_use2( |
| ; CHECK-NEXT: [[WIDECMP:%.*]] = shufflevector <2 x i1> [[CMP:%.*]], <2 x i1> undef, <4 x i32> <i32 0, i32 1, i32 undef, i32 undef> |
| ; CHECK-NEXT: call void @use_cmp(<4 x i1> [[WIDECMP]]) |
| ; CHECK-NEXT: [[WIDESEL:%.*]] = select <4 x i1> [[WIDECMP]], <4 x i8> [[X:%.*]], <4 x i8> [[Y:%.*]] |
| ; CHECK-NEXT: [[R:%.*]] = shufflevector <4 x i8> [[WIDESEL]], <4 x i8> undef, <2 x i32> <i32 0, i32 1> |
| ; CHECK-NEXT: ret <2 x i8> [[R]] |
| ; |
| %widecmp = shufflevector <2 x i1> %cmp, <2 x i1> undef, <4 x i32> <i32 0, i32 1, i32 undef, i32 undef> |
| call void @use_cmp(<4 x i1> %widecmp) |
| %widesel = select <4 x i1> %widecmp, <4 x i8> %x, <4 x i8> %y |
| %r = shufflevector <4 x i8> %widesel, <4 x i8> undef, <2 x i32> <i32 0, i32 1> |
| ret <2 x i8> %r |
| } |
| |
| ; Negative test - mismatched types would require extra shuffling. |
| |
| define <3 x i8> @narrow_shuffle_of_select_mismatch_types1(<2 x i1> %cmp, <4 x i8> %x, <4 x i8> %y) { |
| ; CHECK-LABEL: @narrow_shuffle_of_select_mismatch_types1( |
| ; CHECK-NEXT: [[WIDECMP:%.*]] = shufflevector <2 x i1> [[CMP:%.*]], <2 x i1> undef, <4 x i32> <i32 0, i32 1, i32 undef, i32 undef> |
| ; CHECK-NEXT: [[WIDESEL:%.*]] = select <4 x i1> [[WIDECMP]], <4 x i8> [[X:%.*]], <4 x i8> [[Y:%.*]] |
| ; CHECK-NEXT: [[R:%.*]] = shufflevector <4 x i8> [[WIDESEL]], <4 x i8> undef, <3 x i32> <i32 0, i32 1, i32 2> |
| ; CHECK-NEXT: ret <3 x i8> [[R]] |
| ; |
| %widecmp = shufflevector <2 x i1> %cmp, <2 x i1> undef, <4 x i32> <i32 0, i32 1, i32 undef, i32 undef> |
| %widesel = select <4 x i1> %widecmp, <4 x i8> %x, <4 x i8> %y |
| %r = shufflevector <4 x i8> %widesel, <4 x i8> undef, <3 x i32> <i32 0, i32 1, i32 2> |
| ret <3 x i8> %r |
| } |
| |
| ; Negative test - mismatched types would require extra shuffling. |
| |
| define <3 x i8> @narrow_shuffle_of_select_mismatch_types2(<4 x i1> %cmp, <6 x i8> %x, <6 x i8> %y) { |
| ; CHECK-LABEL: @narrow_shuffle_of_select_mismatch_types2( |
| ; CHECK-NEXT: [[WIDECMP:%.*]] = shufflevector <4 x i1> [[CMP:%.*]], <4 x i1> undef, <6 x i32> <i32 0, i32 1, i32 2, i32 undef, i32 undef, i32 undef> |
| ; CHECK-NEXT: [[WIDESEL:%.*]] = select <6 x i1> [[WIDECMP]], <6 x i8> [[X:%.*]], <6 x i8> [[Y:%.*]] |
| ; CHECK-NEXT: [[R:%.*]] = shufflevector <6 x i8> [[WIDESEL]], <6 x i8> undef, <3 x i32> <i32 0, i32 1, i32 2> |
| ; CHECK-NEXT: ret <3 x i8> [[R]] |
| ; |
| %widecmp = shufflevector <4 x i1> %cmp, <4 x i1> undef, <6 x i32> <i32 0, i32 1, i32 2, i32 3, i32 undef, i32 undef> |
| %widesel = select <6 x i1> %widecmp, <6 x i8> %x, <6 x i8> %y |
| %r = shufflevector <6 x i8> %widesel, <6 x i8> undef, <3 x i32> <i32 0, i32 1, i32 2> |
| ret <3 x i8> %r |
| } |
| |
| ; Narrowing constants does not require creating new narrowing shuffle instructions. |
| |
| define <2 x i8> @narrow_shuffle_of_select_consts(<2 x i1> %cmp) { |
| ; CHECK-LABEL: @narrow_shuffle_of_select_consts( |
| ; CHECK-NEXT: [[R:%.*]] = select <2 x i1> [[CMP:%.*]], <2 x i8> <i8 -1, i8 -2>, <2 x i8> <i8 1, i8 2> |
| ; CHECK-NEXT: ret <2 x i8> [[R]] |
| ; |
| %widecmp = shufflevector <2 x i1> %cmp, <2 x i1> undef, <4 x i32> <i32 0, i32 1, i32 undef, i32 undef> |
| %widesel = select <4 x i1> %widecmp, <4 x i8> <i8 -1, i8 -2, i8 -3, i8 -4>, <4 x i8> <i8 1, i8 2, i8 3, i8 4> |
| %r = shufflevector <4 x i8> %widesel, <4 x i8> undef, <2 x i32> <i32 0, i32 1> |
| ret <2 x i8> %r |
| } |
| |
| ; PR38691 - https://bugs.llvm.org/show_bug.cgi?id=38691 |
| ; If the operands are widened only to be narrowed back, then all of the shuffles are unnecessary. |
| |
| define <2 x i8> @narrow_shuffle_of_select_with_widened_ops(<2 x i1> %cmp, <2 x i8> %x, <2 x i8> %y) { |
| ; CHECK-LABEL: @narrow_shuffle_of_select_with_widened_ops( |
| ; CHECK-NEXT: [[R:%.*]] = select <2 x i1> [[CMP:%.*]], <2 x i8> [[X:%.*]], <2 x i8> [[Y:%.*]] |
| ; CHECK-NEXT: ret <2 x i8> [[R]] |
| ; |
| %widex = shufflevector <2 x i8> %x, <2 x i8> undef, <4 x i32> <i32 0, i32 1, i32 undef, i32 undef> |
| %widey = shufflevector <2 x i8> %y, <2 x i8> undef, <4 x i32> <i32 0, i32 1, i32 undef, i32 undef> |
| %widecmp = shufflevector <2 x i1> %cmp, <2 x i1> undef, <4 x i32> <i32 0, i32 1, i32 undef, i32 undef> |
| %widesel = select <4 x i1> %widecmp, <4 x i8> %widex, <4 x i8> %widey |
| %r = shufflevector <4 x i8> %widesel, <4 x i8> undef, <2 x i32> <i32 0, i32 1> |
| ret <2 x i8> %r |
| } |
| |