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| ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s -mtriple=arm-eabi-unknown-unknown | FileCheck %s
; Select of constants: control flow / conditional moves can always be replaced by logic+math (but may not be worth it?).
; Test the zeroext/signext variants of each pattern to see if that makes a difference.
; select Cond, 0, 1 --> zext (!Cond)
define i32 @select_0_or_1(i1 %cond) {
; CHECK-LABEL: select_0_or_1:
; CHECK: @ %bb.0:
; CHECK-NEXT: mov r1, #1
; CHECK-NEXT: bic r0, r1, r0
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 0, i32 1
ret i32 %sel
}
define i32 @select_0_or_1_zeroext(i1 zeroext %cond) {
; CHECK-LABEL: select_0_or_1_zeroext:
; CHECK: @ %bb.0:
; CHECK-NEXT: eor r0, r0, #1
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 0, i32 1
ret i32 %sel
}
define i32 @select_0_or_1_signext(i1 signext %cond) {
; CHECK-LABEL: select_0_or_1_signext:
; CHECK: @ %bb.0:
; CHECK-NEXT: mov r1, #1
; CHECK-NEXT: bic r0, r1, r0
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 0, i32 1
ret i32 %sel
}
; select Cond, 1, 0 --> zext (Cond)
define i32 @select_1_or_0(i1 %cond) {
; CHECK-LABEL: select_1_or_0:
; CHECK: @ %bb.0:
; CHECK-NEXT: and r0, r0, #1
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 1, i32 0
ret i32 %sel
}
define i32 @select_1_or_0_zeroext(i1 zeroext %cond) {
; CHECK-LABEL: select_1_or_0_zeroext:
; CHECK: @ %bb.0:
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 1, i32 0
ret i32 %sel
}
define i32 @select_1_or_0_signext(i1 signext %cond) {
; CHECK-LABEL: select_1_or_0_signext:
; CHECK: @ %bb.0:
; CHECK-NEXT: and r0, r0, #1
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 1, i32 0
ret i32 %sel
}
; select Cond, 0, -1 --> sext (!Cond)
define i32 @select_0_or_neg1(i1 %cond) {
; CHECK-LABEL: select_0_or_neg1:
; CHECK: @ %bb.0:
; CHECK-NEXT: mov r1, #1
; CHECK-NEXT: bic r0, r1, r0
; CHECK-NEXT: rsb r0, r0, #0
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 0, i32 -1
ret i32 %sel
}
define i32 @select_0_or_neg1_zeroext(i1 zeroext %cond) {
; CHECK-LABEL: select_0_or_neg1_zeroext:
; CHECK: @ %bb.0:
; CHECK-NEXT: eor r0, r0, #1
; CHECK-NEXT: rsb r0, r0, #0
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 0, i32 -1
ret i32 %sel
}
define i32 @select_0_or_neg1_signext(i1 signext %cond) {
; CHECK-LABEL: select_0_or_neg1_signext:
; CHECK: @ %bb.0:
; CHECK-NEXT: mvn r0, r0
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 0, i32 -1
ret i32 %sel
}
define i32 @select_0_or_neg1_alt(i1 %cond) {
; CHECK-LABEL: select_0_or_neg1_alt:
; CHECK: @ %bb.0:
; CHECK-NEXT: and r0, r0, #1
; CHECK-NEXT: sub r0, r0, #1
; CHECK-NEXT: mov pc, lr
%z = zext i1 %cond to i32
%add = add i32 %z, -1
ret i32 %add
}
define i32 @select_0_or_neg1_alt_zeroext(i1 zeroext %cond) {
; CHECK-LABEL: select_0_or_neg1_alt_zeroext:
; CHECK: @ %bb.0:
; CHECK-NEXT: sub r0, r0, #1
; CHECK-NEXT: mov pc, lr
%z = zext i1 %cond to i32
%add = add i32 %z, -1
ret i32 %add
}
define i32 @select_0_or_neg1_alt_signext(i1 signext %cond) {
; CHECK-LABEL: select_0_or_neg1_alt_signext:
; CHECK: @ %bb.0:
; CHECK-NEXT: mvn r0, r0
; CHECK-NEXT: mov pc, lr
%z = zext i1 %cond to i32
%add = add i32 %z, -1
ret i32 %add
}
; select Cond, -1, 0 --> sext (Cond)
define i32 @select_neg1_or_0(i1 %cond) {
; CHECK-LABEL: select_neg1_or_0:
; CHECK: @ %bb.0:
; CHECK-NEXT: and r0, r0, #1
; CHECK-NEXT: rsb r0, r0, #0
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 -1, i32 0
ret i32 %sel
}
define i32 @select_neg1_or_0_zeroext(i1 zeroext %cond) {
; CHECK-LABEL: select_neg1_or_0_zeroext:
; CHECK: @ %bb.0:
; CHECK-NEXT: rsb r0, r0, #0
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 -1, i32 0
ret i32 %sel
}
define i32 @select_neg1_or_0_signext(i1 signext %cond) {
; CHECK-LABEL: select_neg1_or_0_signext:
; CHECK: @ %bb.0:
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 -1, i32 0
ret i32 %sel
}
; select Cond, C+1, C --> add (zext Cond), C
define i32 @select_Cplus1_C(i1 %cond) {
; CHECK-LABEL: select_Cplus1_C:
; CHECK: @ %bb.0:
; CHECK-NEXT: mov r1, #41
; CHECK-NEXT: tst r0, #1
; CHECK-NEXT: movne r1, #42
; CHECK-NEXT: mov r0, r1
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 42, i32 41
ret i32 %sel
}
define i32 @select_Cplus1_C_zeroext(i1 zeroext %cond) {
; CHECK-LABEL: select_Cplus1_C_zeroext:
; CHECK: @ %bb.0:
; CHECK-NEXT: mov r1, #41
; CHECK-NEXT: cmp r0, #0
; CHECK-NEXT: movne r1, #42
; CHECK-NEXT: mov r0, r1
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 42, i32 41
ret i32 %sel
}
define i32 @select_Cplus1_C_signext(i1 signext %cond) {
; CHECK-LABEL: select_Cplus1_C_signext:
; CHECK: @ %bb.0:
; CHECK-NEXT: mov r1, #41
; CHECK-NEXT: tst r0, #1
; CHECK-NEXT: movne r1, #42
; CHECK-NEXT: mov r0, r1
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 42, i32 41
ret i32 %sel
}
; select Cond, C, C+1 --> add (sext Cond), C
define i32 @select_C_Cplus1(i1 %cond) {
; CHECK-LABEL: select_C_Cplus1:
; CHECK: @ %bb.0:
; CHECK-NEXT: mov r1, #42
; CHECK-NEXT: tst r0, #1
; CHECK-NEXT: movne r1, #41
; CHECK-NEXT: mov r0, r1
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 41, i32 42
ret i32 %sel
}
define i32 @select_C_Cplus1_zeroext(i1 zeroext %cond) {
; CHECK-LABEL: select_C_Cplus1_zeroext:
; CHECK: @ %bb.0:
; CHECK-NEXT: mov r1, #42
; CHECK-NEXT: cmp r0, #0
; CHECK-NEXT: movne r1, #41
; CHECK-NEXT: mov r0, r1
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 41, i32 42
ret i32 %sel
}
define i32 @select_C_Cplus1_signext(i1 signext %cond) {
; CHECK-LABEL: select_C_Cplus1_signext:
; CHECK: @ %bb.0:
; CHECK-NEXT: mov r1, #42
; CHECK-NEXT: tst r0, #1
; CHECK-NEXT: movne r1, #41
; CHECK-NEXT: mov r0, r1
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 41, i32 42
ret i32 %sel
}
; In general, select of 2 constants could be:
; select Cond, C1, C2 --> add (mul (zext Cond), C1-C2), C2 --> add (and (sext Cond), C1-C2), C2
define i32 @select_C1_C2(i1 %cond) {
; CHECK-LABEL: select_C1_C2:
; CHECK: @ %bb.0:
; CHECK-NEXT: mov r1, #165
; CHECK-NEXT: tst r0, #1
; CHECK-NEXT: orr r1, r1, #256
; CHECK-NEXT: moveq r1, #42
; CHECK-NEXT: mov r0, r1
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 421, i32 42
ret i32 %sel
}
define i32 @select_C1_C2_zeroext(i1 zeroext %cond) {
; CHECK-LABEL: select_C1_C2_zeroext:
; CHECK: @ %bb.0:
; CHECK-NEXT: mov r1, #165
; CHECK-NEXT: cmp r0, #0
; CHECK-NEXT: orr r1, r1, #256
; CHECK-NEXT: moveq r1, #42
; CHECK-NEXT: mov r0, r1
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 421, i32 42
ret i32 %sel
}
define i32 @select_C1_C2_signext(i1 signext %cond) {
; CHECK-LABEL: select_C1_C2_signext:
; CHECK: @ %bb.0:
; CHECK-NEXT: mov r1, #165
; CHECK-NEXT: tst r0, #1
; CHECK-NEXT: orr r1, r1, #256
; CHECK-NEXT: moveq r1, #42
; CHECK-NEXT: mov r0, r1
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 421, i32 42
ret i32 %sel
}
; 4295032833 = 0x100010001.
; This becomes an opaque constant via ConstantHoisting, so we don't fold it into the select.
define i64 @opaque_constant1(i1 %cond, i64 %x) {
; CHECK-LABEL: opaque_constant1:
; CHECK: @ %bb.0:
; CHECK-NEXT: .save {r4, lr}
; CHECK-NEXT: push {r4, lr}
; CHECK-NEXT: mov lr, #1
; CHECK-NEXT: ands r12, r0, #1
; CHECK-NEXT: mov r0, #23
; CHECK-NEXT: orr lr, lr, #65536
; CHECK-NEXT: mvnne r0, #3
; CHECK-NEXT: and r4, r0, lr
; CHECK-NEXT: movne r12, #1
; CHECK-NEXT: subs r0, r4, #1
; CHECK-NEXT: eor r2, r2, lr
; CHECK-NEXT: eor r3, r3, #1
; CHECK-NEXT: sbc r1, r12, #0
; CHECK-NEXT: orrs r2, r2, r3
; CHECK-NEXT: movne r0, r4
; CHECK-NEXT: movne r1, r12
; CHECK-NEXT: pop {r4, lr}
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i64 -4, i64 23
%bo = and i64 %sel, 4295032833 ; 0x100010001
%cmp = icmp eq i64 %x, 4295032833
%sext = sext i1 %cmp to i64
%add = add i64 %bo, %sext
ret i64 %add
}
; 65537 == 0x10001.
; This becomes an opaque constant via ConstantHoisting, so we don't fold it into the select.
define i64 @opaque_constant2(i1 %cond, i64 %x) {
; CHECK-LABEL: opaque_constant2:
; CHECK: @ %bb.0:
; CHECK-NEXT: mov r1, #1
; CHECK-NEXT: tst r0, #1
; CHECK-NEXT: orr r1, r1, #65536
; CHECK-NEXT: moveq r1, #23
; CHECK-NEXT: bic r0, r1, #22
; CHECK-NEXT: mov r1, #0
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i64 65537, i64 23
%bo = and i64 %sel, 65537
ret i64 %bo
}
|