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clang-p2996/llvm/test/Transforms/InstCombine/icmp-select.ll
Nikita Popov a105877646 [InstCombine] Remove some of the complexity-based canonicalization (#91185) 
The idea behind this canonicalization is that it allows us to handle less
patterns, because we know that some will be canonicalized away. This is
indeed very useful to e.g. know that constants are always on the right.

However, this is only useful if the canonicalization is actually
reliable. This is the case for constants, but not for arguments: Moving
these to the right makes it look like the "more complex" expression is
guaranteed to be on the left, but this is not actually the case in
practice. It fails as soon as you replace the argument with another
instruction.

The end result is that it looks like things correctly work in tests,
while they actually don't. We use the "thwart complexity-based
canonicalization" trick to handle this in tests, but it's often a
challenge for new contributors to get this right, and based on the
regressions this PR originally exposed, we clearly don't get this right
in many cases.

For this reason, I think that it's better to remove this complexity
canonicalization. It will make it much easier to write tests for
commuted cases and make sure that they are handled.
2024-08-21 12:02:54 +02:00

631 lines
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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -S -passes=instcombine < %s | FileCheck %s
declare void @use(i8)
declare void @use.i1(i1)
declare i8 @llvm.umin.i8(i8, i8)
define i1 @icmp_select_const(i8 %x, i8 %y) {
; CHECK-LABEL: @icmp_select_const(
; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT: [[CMP21:%.*]] = icmp eq i8 [[Y:%.*]], 0
; CHECK-NEXT: [[CMP2:%.*]] = select i1 [[CMP1]], i1 true, i1 [[CMP21]]
; CHECK-NEXT: ret i1 [[CMP2]]
;
%cmp1 = icmp eq i8 %x, 0
%sel = select i1 %cmp1, i8 0, i8 %y
%cmp2 = icmp eq i8 %sel, 0
ret i1 %cmp2
}
define i1 @icmp_select_var(i8 %x, i8 %y, i8 %z) {
; CHECK-LABEL: @icmp_select_var(
; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT: [[CMP21:%.*]] = icmp eq i8 [[Y:%.*]], [[Z:%.*]]
; CHECK-NEXT: [[CMP2:%.*]] = select i1 [[CMP1]], i1 true, i1 [[CMP21]]
; CHECK-NEXT: ret i1 [[CMP2]]
;
%cmp1 = icmp eq i8 %x, 0
%sel = select i1 %cmp1, i8 %z, i8 %y
%cmp2 = icmp eq i8 %sel, %z
ret i1 %cmp2
}
define i1 @icmp_select_var_commuted(i8 %x, i8 %y, i8 %_z) {
; CHECK-LABEL: @icmp_select_var_commuted(
; CHECK-NEXT: [[Z:%.*]] = udiv i8 42, [[_Z:%.*]]
; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT: [[CMP21:%.*]] = icmp eq i8 [[Y:%.*]], [[Z]]
; CHECK-NEXT: [[CMP2:%.*]] = select i1 [[CMP1]], i1 true, i1 [[CMP21]]
; CHECK-NEXT: ret i1 [[CMP2]]
;
%z = udiv i8 42, %_z ; thwart complexity-based canonicalization
%cmp1 = icmp eq i8 %x, 0
%sel = select i1 %cmp1, i8 %z, i8 %y
%cmp2 = icmp eq i8 %z, %sel
ret i1 %cmp2
}
define i1 @icmp_select_var_select(i8 %x, i8 %y, i1 %c) {
; CHECK-LABEL: @icmp_select_var_select(
; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT: [[CMP212:%.*]] = icmp eq i8 [[X]], [[Y:%.*]]
; CHECK-NEXT: [[NOT_C:%.*]] = xor i1 [[C:%.*]], true
; CHECK-NEXT: [[TMP1:%.*]] = select i1 [[CMP1]], i1 true, i1 [[NOT_C]]
; CHECK-NEXT: [[CMP2:%.*]] = select i1 [[TMP1]], i1 true, i1 [[CMP212]]
; CHECK-NEXT: ret i1 [[CMP2]]
;
%z = select i1 %c, i8 %x, i8 %y
%cmp1 = icmp eq i8 %x, 0
%sel = select i1 %cmp1, i8 %z, i8 %y
%cmp2 = icmp eq i8 %z, %sel
ret i1 %cmp2
}
define i1 @icmp_select_var_both_fold(i8 %x, i8 %y, i8 %_z) {
; CHECK-LABEL: @icmp_select_var_both_fold(
; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT: ret i1 [[CMP1]]
;
%z = or i8 %_z, 1
%cmp1 = icmp eq i8 %x, 0
%sel = select i1 %cmp1, i8 %z, i8 2
%cmp2 = icmp eq i8 %sel, %z
ret i1 %cmp2
}
define i1 @icmp_select_var_extra_use(i8 %x, i8 %y, i8 %z) {
; CHECK-LABEL: @icmp_select_var_extra_use(
; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1]], i8 [[Z:%.*]], i8 [[Y:%.*]]
; CHECK-NEXT: call void @use(i8 [[SEL]])
; CHECK-NEXT: [[CMP2:%.*]] = icmp eq i8 [[SEL]], [[Z]]
; CHECK-NEXT: ret i1 [[CMP2]]
;
%cmp1 = icmp eq i8 %x, 0
%sel = select i1 %cmp1, i8 %z, i8 %y
call void @use(i8 %sel)
%cmp2 = icmp eq i8 %sel, %z
ret i1 %cmp2
}
define i1 @icmp_select_var_both_fold_extra_use(i8 %x, i8 %y, i8 %_z) {
; CHECK-LABEL: @icmp_select_var_both_fold_extra_use(
; CHECK-NEXT: [[Z:%.*]] = or i8 [[_Z:%.*]], 1
; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1]], i8 [[Z]], i8 2
; CHECK-NEXT: call void @use(i8 [[SEL]])
; CHECK-NEXT: ret i1 [[CMP1]]
;
%z = or i8 %_z, 1
%cmp1 = icmp eq i8 %x, 0
%sel = select i1 %cmp1, i8 %z, i8 2
call void @use(i8 %sel)
%cmp2 = icmp eq i8 %sel, %z
ret i1 %cmp2
}
define i1 @icmp_select_var_pred_ne(i8 %x, i8 %y, i8 %z) {
; CHECK-LABEL: @icmp_select_var_pred_ne(
; CHECK-NEXT: [[CMP1:%.*]] = icmp ne i8 [[X:%.*]], 0
; CHECK-NEXT: [[CMP21:%.*]] = icmp ne i8 [[Y:%.*]], [[Z:%.*]]
; CHECK-NEXT: [[CMP2:%.*]] = select i1 [[CMP1]], i1 [[CMP21]], i1 false
; CHECK-NEXT: ret i1 [[CMP2]]
;
%cmp1 = icmp eq i8 %x, 0
%sel = select i1 %cmp1, i8 %z, i8 %y
%cmp2 = icmp ne i8 %sel, %z
ret i1 %cmp2
}
define i1 @icmp_select_var_pred_ult(i8 %x, i8 %y, i8 %z) {
; CHECK-LABEL: @icmp_select_var_pred_ult(
; CHECK-NEXT: [[Z1:%.*]] = add nuw i8 [[Z:%.*]], 2
; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT: [[CMP21:%.*]] = icmp ult i8 [[Y:%.*]], [[Z1]]
; CHECK-NEXT: [[CMP2:%.*]] = select i1 [[CMP1]], i1 true, i1 [[CMP21]]
; CHECK-NEXT: ret i1 [[CMP2]]
;
%z1 = add nuw i8 %z, 2
%cmp1 = icmp eq i8 %x, 0
%sel = select i1 %cmp1, i8 %z, i8 %y
%cmp2 = icmp ult i8 %sel, %z1
ret i1 %cmp2
}
define i1 @icmp_select_var_pred_uge(i8 %x, i8 %y, i8 %z) {
; CHECK-LABEL: @icmp_select_var_pred_uge(
; CHECK-NEXT: [[Z1:%.*]] = add nuw i8 [[Z:%.*]], 2
; CHECK-NEXT: [[CMP1:%.*]] = icmp ne i8 [[X:%.*]], 0
; CHECK-NEXT: [[CMP21:%.*]] = icmp uge i8 [[Y:%.*]], [[Z1]]
; CHECK-NEXT: [[CMP2:%.*]] = select i1 [[CMP1]], i1 [[CMP21]], i1 false
; CHECK-NEXT: ret i1 [[CMP2]]
;
%z1 = add nuw i8 %z, 2
%cmp1 = icmp eq i8 %x, 0
%sel = select i1 %cmp1, i8 %z, i8 %y
%cmp2 = icmp uge i8 %sel, %z1
ret i1 %cmp2
}
define i1 @icmp_select_var_pred_uge_commuted(i8 %x, i8 %y, i8 %z) {
; CHECK-LABEL: @icmp_select_var_pred_uge_commuted(
; CHECK-NEXT: [[Z1:%.*]] = add nuw i8 [[Z:%.*]], 2
; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT: [[CMP21:%.*]] = icmp ule i8 [[Y:%.*]], [[Z1]]
; CHECK-NEXT: [[CMP2:%.*]] = select i1 [[CMP1]], i1 true, i1 [[CMP21]]
; CHECK-NEXT: ret i1 [[CMP2]]
;
%z1 = add nuw i8 %z, 2
%cmp1 = icmp eq i8 %x, 0
%sel = select i1 %cmp1, i8 %z, i8 %y
%cmp2 = icmp uge i8 %z1, %sel
ret i1 %cmp2
}
define i1 @icmp_select_implied_cond(i8 %x, i8 %y) {
; CHECK-LABEL: @icmp_select_implied_cond(
; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT: [[CMP21:%.*]] = icmp eq i8 [[Y:%.*]], [[X]]
; CHECK-NEXT: [[CMP2:%.*]] = select i1 [[CMP1]], i1 true, i1 [[CMP21]]
; CHECK-NEXT: ret i1 [[CMP2]]
;
%cmp1 = icmp eq i8 %x, 0
%sel = select i1 %cmp1, i8 0, i8 %y
%cmp2 = icmp eq i8 %sel, %x
ret i1 %cmp2
}
define i1 @icmp_select_implied_cond_ne(i8 %x, i8 %y) {
; CHECK-LABEL: @icmp_select_implied_cond_ne(
; CHECK-NEXT: [[CMP1:%.*]] = icmp ne i8 [[X:%.*]], 0
; CHECK-NEXT: [[CMP21:%.*]] = icmp ne i8 [[Y:%.*]], [[X]]
; CHECK-NEXT: [[CMP2:%.*]] = select i1 [[CMP1]], i1 [[CMP21]], i1 false
; CHECK-NEXT: ret i1 [[CMP2]]
;
%cmp1 = icmp eq i8 %x, 0
%sel = select i1 %cmp1, i8 0, i8 %y
%cmp2 = icmp ne i8 %sel, %x
ret i1 %cmp2
}
define i1 @icmp_select_implied_cond_swapped_select(i8 %x, i8 %y) {
; CHECK-LABEL: @icmp_select_implied_cond_swapped_select(
; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i8 [[Y:%.*]], 0
; CHECK-NEXT: [[CMP2:%.*]] = select i1 [[CMP1]], i1 [[TMP1]], i1 false
; CHECK-NEXT: ret i1 [[CMP2]]
;
%cmp1 = icmp eq i8 %x, 0
%sel = select i1 %cmp1, i8 %y, i8 0
%cmp2 = icmp eq i8 %sel, %x
ret i1 %cmp2
}
define i1 @icmp_select_implied_cond_swapped_select_with_inv_cond(i8 %x, i8 %y) {
; CHECK-LABEL: @icmp_select_implied_cond_swapped_select_with_inv_cond(
; CHECK-NEXT: [[CMP1:%.*]] = icmp ne i8 [[X:%.*]], 0
; CHECK-NEXT: call void @use.i1(i1 [[CMP1]])
; CHECK-NEXT: [[CMP21:%.*]] = icmp eq i8 [[Y:%.*]], [[X]]
; CHECK-NEXT: [[NOT_CMP1:%.*]] = xor i1 [[CMP1]], true
; CHECK-NEXT: [[CMP2:%.*]] = select i1 [[NOT_CMP1]], i1 true, i1 [[CMP21]]
; CHECK-NEXT: ret i1 [[CMP2]]
;
%cmp1 = icmp ne i8 %x, 0
call void @use.i1(i1 %cmp1)
%sel = select i1 %cmp1, i8 %y, i8 0
%cmp2 = icmp eq i8 %sel, %x
ret i1 %cmp2
}
define i1 @icmp_select_implied_cond_relational(i8 %x, i8 %y) {
; CHECK-LABEL: @icmp_select_implied_cond_relational(
; CHECK-NEXT: [[CMP1:%.*]] = icmp ugt i8 [[X:%.*]], 10
; CHECK-NEXT: [[CMP21:%.*]] = icmp ult i8 [[Y:%.*]], [[X]]
; CHECK-NEXT: [[CMP2:%.*]] = select i1 [[CMP1]], i1 true, i1 [[CMP21]]
; CHECK-NEXT: ret i1 [[CMP2]]
;
%cmp1 = icmp ugt i8 %x, 10
%sel = select i1 %cmp1, i8 10, i8 %y
%cmp2 = icmp ult i8 %sel, %x
ret i1 %cmp2
}
define i1 @icmp_select_implied_cond_relational_off_by_one(i8 %x, i8 %y) {
; CHECK-LABEL: @icmp_select_implied_cond_relational_off_by_one(
; CHECK-NEXT: [[CMP1:%.*]] = icmp ugt i8 [[X:%.*]], 10
; CHECK-NEXT: call void @use.i1(i1 [[CMP1]])
; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1]], i8 11, i8 [[Y:%.*]]
; CHECK-NEXT: [[CMP2:%.*]] = icmp ult i8 [[SEL]], [[X]]
; CHECK-NEXT: ret i1 [[CMP2]]
;
%cmp1 = icmp ugt i8 %x, 10
call void @use.i1(i1 %cmp1)
%sel = select i1 %cmp1, i8 11, i8 %y
%cmp2 = icmp ult i8 %sel, %x
ret i1 %cmp2
}
define i1 @umin_seq_comparison(i8 %x, i8 %y) {
; CHECK-LABEL: @umin_seq_comparison(
; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT: [[CMP21:%.*]] = icmp ule i8 [[X]], [[Y:%.*]]
; CHECK-NEXT: [[CMP2:%.*]] = select i1 [[CMP1]], i1 true, i1 [[CMP21]]
; CHECK-NEXT: ret i1 [[CMP2]]
;
%min = call i8 @llvm.umin.i8(i8 %x, i8 %y)
%cmp1 = icmp eq i8 %x, 0
%sel = select i1 %cmp1, i8 0, i8 %min
%cmp2 = icmp eq i8 %sel, %x
ret i1 %cmp2
}
; ((A ? TC : FC) & (B ? TC : FC)) == 0 --> xor A, B
define i1 @select_constants_and_icmp_eq0(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_eq0(
; CHECK-NEXT: [[CMP:%.*]] = xor i1 [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT: ret i1 [[CMP]]
;
%s1 = select i1 %x, i8 2, i8 1
%s2 = select i1 %y, i8 2, i8 1
%and = and i8 %s1, %s2
%cmp = icmp eq i8 %and, 0
ret i1 %cmp
}
; extra uses on all intermediates are ok
define i1 @select_constants_and_icmp_eq0_uses(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_eq0_uses(
; CHECK-NEXT: [[S1:%.*]] = select i1 [[X:%.*]], i8 2, i8 1
; CHECK-NEXT: call void @use(i8 [[S1]])
; CHECK-NEXT: [[S2:%.*]] = select i1 [[Y:%.*]], i8 2, i8 1
; CHECK-NEXT: call void @use(i8 [[S2]])
; CHECK-NEXT: [[AND:%.*]] = and i8 [[S1]], [[S2]]
; CHECK-NEXT: call void @use(i8 [[AND]])
; CHECK-NEXT: [[CMP:%.*]] = xor i1 [[X]], [[Y]]
; CHECK-NEXT: ret i1 [[CMP]]
;
%s1 = select i1 %x, i8 2, i8 1
call void @use(i8 %s1)
%s2 = select i1 %y, i8 2, i8 1
call void @use(i8 %s2)
%and = and i8 %s1, %s2
call void @use(i8 %and)
%cmp = icmp eq i8 %and, 0
ret i1 %cmp
}
; vector splat constants are ok
define <2 x i1> @select_constants_and_icmp_eq0_vec_splat(<2 x i1> %x, <2 x i1> %y) {
; CHECK-LABEL: @select_constants_and_icmp_eq0_vec_splat(
; CHECK-NEXT: [[CMP:%.*]] = xor <2 x i1> [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT: ret <2 x i1> [[CMP]]
;
%s1 = select <2 x i1> %x, <2 x i9> <i9 3, i9 3>, <2 x i9> <i9 48, i9 48>
%s2 = select <2 x i1> %y, <2 x i9> <i9 3, i9 3>, <2 x i9> <i9 48, i9 48>
%and = and <2 x i9> %s1, %s2
%cmp = icmp eq <2 x i9> %and, zeroinitializer
ret <2 x i1> %cmp
}
; common bit set - simplified via known bits
define i1 @select_constants_and_icmp_eq0_common_bit(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_eq0_common_bit(
; CHECK-NEXT: ret i1 false
;
%s1 = select i1 %x, i8 2, i8 3
%s2 = select i1 %y, i8 2, i8 3
%and = and i8 %s1, %s2
%cmp = icmp eq i8 %and, 0
ret i1 %cmp
}
; negative test - need matching constants
define i1 @select_constants_and_icmp_eq0_no_common_op1(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_eq0_no_common_op1(
; CHECK-NEXT: [[S1:%.*]] = select i1 [[X:%.*]], i8 16, i8 3
; CHECK-NEXT: [[S2:%.*]] = select i1 [[Y:%.*]], i8 24, i8 3
; CHECK-NEXT: [[AND:%.*]] = and i8 [[S1]], [[S2]]
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i8 [[AND]], 0
; CHECK-NEXT: ret i1 [[CMP]]
;
%s1 = select i1 %x, i8 16, i8 3
%s2 = select i1 %y, i8 24, i8 3
%and = and i8 %s1, %s2
%cmp = icmp eq i8 %and, 0
ret i1 %cmp
}
; negative test - need matching constants
define i1 @select_constants_and_icmp_eq0_no_common_op2(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_eq0_no_common_op2(
; CHECK-NEXT: [[S1:%.*]] = select i1 [[X:%.*]], i8 16, i8 3
; CHECK-NEXT: [[S2:%.*]] = select i1 [[Y:%.*]], i8 16, i8 7
; CHECK-NEXT: [[AND:%.*]] = and i8 [[S1]], [[S2]]
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i8 [[AND]], 0
; CHECK-NEXT: ret i1 [[CMP]]
;
%s1 = select i1 %x, i8 16, i8 3
%s2 = select i1 %y, i8 16, i8 7
%and = and i8 %s1, %s2
%cmp = icmp eq i8 %and, 0
ret i1 %cmp
}
; reduces via FoldOpInstSelect, but this could be a simple 'or'
define i1 @select_constants_and_icmp_eq0_zero_tval(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_eq0_zero_tval(
; CHECK-NEXT: [[TMP1:%.*]] = select i1 [[X:%.*]], i1 true, i1 [[Y:%.*]]
; CHECK-NEXT: ret i1 [[TMP1]]
;
%s1 = select i1 %x, i8 0, i8 12
%s2 = select i1 %y, i8 0, i8 12
%and = and i8 %s1, %s2
%cmp = icmp eq i8 %and, 0
ret i1 %cmp
}
; reduces via FoldOpInstSelect, but this could be a simple 'not-of-and'
define i1 @select_constants_and_icmp_eq0_zero_fval(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_eq0_zero_fval(
; CHECK-NEXT: [[TMP1:%.*]] = select i1 [[X:%.*]], i1 [[Y:%.*]], i1 false
; CHECK-NEXT: [[NOT_:%.*]] = xor i1 [[TMP1]], true
; CHECK-NEXT: ret i1 [[NOT_]]
;
%s1 = select i1 %x, i8 12, i8 0
%s2 = select i1 %y, i8 12, i8 0
%and = and i8 %s1, %s2
%cmp = icmp eq i8 %and, 0
ret i1 %cmp
}
; TODO: x & y
define i1 @select_constants_and_icmp_eq_tval(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_eq_tval(
; CHECK-NEXT: [[S1:%.*]] = select i1 [[X:%.*]], i8 6, i8 1
; CHECK-NEXT: [[S2:%.*]] = select i1 [[Y:%.*]], i8 6, i8 1
; CHECK-NEXT: [[AND:%.*]] = and i8 [[S1]], [[S2]]
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i8 [[AND]], 6
; CHECK-NEXT: ret i1 [[CMP]]
;
%s1 = select i1 %x, i8 6, i8 1
%s2 = select i1 %y, i8 6, i8 1
%and = and i8 %s1, %s2
%cmp = icmp eq i8 %and, 6
ret i1 %cmp
}
; TODO: ~(x | y)
define i1 @select_constants_and_icmp_eq_fval(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_eq_fval(
; CHECK-NEXT: [[S1:%.*]] = select i1 [[X:%.*]], i8 12, i8 3
; CHECK-NEXT: [[S2:%.*]] = select i1 [[Y:%.*]], i8 12, i8 3
; CHECK-NEXT: [[AND:%.*]] = and i8 [[S1]], [[S2]]
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i8 [[AND]], 3
; CHECK-NEXT: ret i1 [[CMP]]
;
%s1 = select i1 %x, i8 12, i8 3
%s2 = select i1 %y, i8 12, i8 3
%and = and i8 %s1, %s2
%cmp = icmp eq i8 %and, 3
ret i1 %cmp
}
; ((A ? TC : FC) & (B ? TC : FC)) != 0 --> not(xor A, B)
define i1 @select_constants_and_icmp_ne0(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_ne0(
; CHECK-NEXT: [[TMP1:%.*]] = xor i1 [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT: [[CMP:%.*]] = xor i1 [[TMP1]], true
; CHECK-NEXT: ret i1 [[CMP]]
;
%s1 = select i1 %x, i8 2, i8 1
%s2 = select i1 %y, i8 2, i8 1
%and = and i8 %s1, %s2
%cmp = icmp ne i8 %and, 0
ret i1 %cmp
}
; extra uses on select intermediates are ok
define i1 @select_constants_and_icmp_ne0_uses(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_ne0_uses(
; CHECK-NEXT: [[S1:%.*]] = select i1 [[X:%.*]], i8 2, i8 1
; CHECK-NEXT: call void @use(i8 [[S1]])
; CHECK-NEXT: [[S2:%.*]] = select i1 [[Y:%.*]], i8 2, i8 1
; CHECK-NEXT: call void @use(i8 [[S2]])
; CHECK-NEXT: [[TMP1:%.*]] = xor i1 [[X]], [[Y]]
; CHECK-NEXT: [[CMP:%.*]] = xor i1 [[TMP1]], true
; CHECK-NEXT: ret i1 [[CMP]]
;
%s1 = select i1 %x, i8 2, i8 1
call void @use(i8 %s1)
%s2 = select i1 %y, i8 2, i8 1
call void @use(i8 %s2)
%and = and i8 %s1, %s2
%cmp = icmp ne i8 %and, 0
ret i1 %cmp
}
; negative test - don't create extra instructions
define i1 @select_constants_and_icmp_ne0_all_uses(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_ne0_all_uses(
; CHECK-NEXT: [[S1:%.*]] = select i1 [[X:%.*]], i8 2, i8 1
; CHECK-NEXT: call void @use(i8 [[S1]])
; CHECK-NEXT: [[S2:%.*]] = select i1 [[Y:%.*]], i8 2, i8 1
; CHECK-NEXT: call void @use(i8 [[S2]])
; CHECK-NEXT: [[AND:%.*]] = and i8 [[S1]], [[S2]]
; CHECK-NEXT: call void @use(i8 [[AND]])
; CHECK-NEXT: [[CMP:%.*]] = icmp ne i8 [[AND]], 0
; CHECK-NEXT: ret i1 [[CMP]]
;
%s1 = select i1 %x, i8 2, i8 1
call void @use(i8 %s1)
%s2 = select i1 %y, i8 2, i8 1
call void @use(i8 %s2)
%and = and i8 %s1, %s2
call void @use(i8 %and)
%cmp = icmp ne i8 %and, 0
ret i1 %cmp
}
; vector splat constants are ok
define <2 x i1> @select_constants_and_icmp_ne0_vec_splat(<2 x i1> %x, <2 x i1> %y) {
; CHECK-LABEL: @select_constants_and_icmp_ne0_vec_splat(
; CHECK-NEXT: [[TMP1:%.*]] = xor <2 x i1> [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT: [[CMP:%.*]] = xor <2 x i1> [[TMP1]], <i1 true, i1 true>
; CHECK-NEXT: ret <2 x i1> [[CMP]]
;
%s1 = select <2 x i1> %x, <2 x i9> <i9 3, i9 3>, <2 x i9> <i9 48, i9 48>
%s2 = select <2 x i1> %y, <2 x i9> <i9 3, i9 3>, <2 x i9> <i9 48, i9 48>
%and = and <2 x i9> %s1, %s2
%cmp = icmp ne <2 x i9> %and, zeroinitializer
ret <2 x i1> %cmp
}
; common bit set - simplified via known bits
define i1 @select_constants_and_icmp_ne0_common_bit(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_ne0_common_bit(
; CHECK-NEXT: ret i1 true
;
%s1 = select i1 %x, i8 2, i8 3
%s2 = select i1 %y, i8 2, i8 3
%and = and i8 %s1, %s2
%cmp = icmp ne i8 %and, 0
ret i1 %cmp
}
; negative test - need matching constants
define i1 @select_constants_and_icmp_ne0_no_common_op1(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_ne0_no_common_op1(
; CHECK-NEXT: [[S1:%.*]] = select i1 [[X:%.*]], i8 16, i8 3
; CHECK-NEXT: [[S2:%.*]] = select i1 [[Y:%.*]], i8 24, i8 3
; CHECK-NEXT: [[AND:%.*]] = and i8 [[S1]], [[S2]]
; CHECK-NEXT: [[CMP:%.*]] = icmp ne i8 [[AND]], 0
; CHECK-NEXT: ret i1 [[CMP]]
;
%s1 = select i1 %x, i8 16, i8 3
%s2 = select i1 %y, i8 24, i8 3
%and = and i8 %s1, %s2
%cmp = icmp ne i8 %and, 0
ret i1 %cmp
}
; negative test - need matching constants
define i1 @select_constants_and_icmp_ne0_no_common_op2(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_ne0_no_common_op2(
; CHECK-NEXT: [[S1:%.*]] = select i1 [[X:%.*]], i8 16, i8 3
; CHECK-NEXT: [[S2:%.*]] = select i1 [[Y:%.*]], i8 16, i8 7
; CHECK-NEXT: [[AND:%.*]] = and i8 [[S1]], [[S2]]
; CHECK-NEXT: [[CMP:%.*]] = icmp ne i8 [[AND]], 0
; CHECK-NEXT: ret i1 [[CMP]]
;
%s1 = select i1 %x, i8 16, i8 3
%s2 = select i1 %y, i8 16, i8 7
%and = and i8 %s1, %s2
%cmp = icmp ne i8 %and, 0
ret i1 %cmp
}
; reduces via FoldOpInstSelect, but this could be a simple 'nor'
define i1 @select_constants_and_icmp_ne0_zero_tval(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_ne0_zero_tval(
; CHECK-NEXT: [[TMP1:%.*]] = select i1 [[X:%.*]], i1 true, i1 [[Y:%.*]]
; CHECK-NEXT: [[NOT_:%.*]] = xor i1 [[TMP1]], true
; CHECK-NEXT: ret i1 [[NOT_]]
;
%s1 = select i1 %x, i8 0, i8 12
%s2 = select i1 %y, i8 0, i8 12
%and = and i8 %s1, %s2
%cmp = icmp ne i8 %and, 0
ret i1 %cmp
}
; reduces via FoldOpInstSelect, but this could be a simple 'and'
define i1 @select_constants_and_icmp_ne0_zero_fval(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_ne0_zero_fval(
; CHECK-NEXT: [[TMP1:%.*]] = select i1 [[X:%.*]], i1 [[Y:%.*]], i1 false
; CHECK-NEXT: ret i1 [[TMP1]]
;
%s1 = select i1 %x, i8 12, i8 0
%s2 = select i1 %y, i8 12, i8 0
%and = and i8 %s1, %s2
%cmp = icmp ne i8 %and, 0
ret i1 %cmp
}
; TODO: ~(x & y)
define i1 @select_constants_and_icmp_ne_tval(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_ne_tval(
; CHECK-NEXT: [[S1:%.*]] = select i1 [[X:%.*]], i8 6, i8 1
; CHECK-NEXT: [[S2:%.*]] = select i1 [[Y:%.*]], i8 6, i8 1
; CHECK-NEXT: [[AND:%.*]] = and i8 [[S1]], [[S2]]
; CHECK-NEXT: [[CMP:%.*]] = icmp ne i8 [[AND]], 6
; CHECK-NEXT: ret i1 [[CMP]]
;
%s1 = select i1 %x, i8 6, i8 1
%s2 = select i1 %y, i8 6, i8 1
%and = and i8 %s1, %s2
%cmp = icmp ne i8 %and, 6
ret i1 %cmp
}
; TODO: (x | y)
define i1 @select_constants_and_icmp_ne_fval(i1 %x, i1 %y) {
; CHECK-LABEL: @select_constants_and_icmp_ne_fval(
; CHECK-NEXT: [[S1:%.*]] = select i1 [[X:%.*]], i8 12, i8 3
; CHECK-NEXT: [[S2:%.*]] = select i1 [[Y:%.*]], i8 12, i8 3
; CHECK-NEXT: [[AND:%.*]] = and i8 [[S1]], [[S2]]
; CHECK-NEXT: [[CMP:%.*]] = icmp ne i8 [[AND]], 3
; CHECK-NEXT: ret i1 [[CMP]]
;
%s1 = select i1 %x, i8 12, i8 3
%s2 = select i1 %y, i8 12, i8 3
%and = and i8 %s1, %s2
%cmp = icmp ne i8 %and, 3
ret i1 %cmp
}
define i1 @icmp_eq_select(i1 %cond, i32 %a, i32 %b) {
; CHECK-LABEL: @icmp_eq_select(
; CHECK-NEXT: [[RES:%.*]] = icmp eq i32 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: ret i1 [[RES]]
;
%lhs = select i1 %cond, i32 %a, i32 %b
%rhs = select i1 %cond, i32 %b, i32 %a
%res = icmp eq i32 %lhs, %rhs
ret i1 %res
}
define i1 @icmp_slt_select(i1 %cond, i32 %a, i32 %b) {
; CHECK-LABEL: @icmp_slt_select(
; CHECK-NEXT: [[LHS:%.*]] = select i1 [[COND:%.*]], i32 [[A:%.*]], i32 [[B:%.*]]
; CHECK-NEXT: [[RHS:%.*]] = select i1 [[COND]], i32 [[B]], i32 [[A]]
; CHECK-NEXT: [[RES:%.*]] = icmp slt i32 [[LHS]], [[RHS]]
; CHECK-NEXT: ret i1 [[RES]]
;
%lhs = select i1 %cond, i32 %a, i32 %b
%rhs = select i1 %cond, i32 %b, i32 %a
%res = icmp slt i32 %lhs, %rhs
ret i1 %res
}
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