; 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: ands r0, r0, #1 ; CHECK-NEXT: movne 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: cmp r0, #0 ; CHECK-NEXT: movne r0, #1 ; 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: ands r0, r0, #1 ; CHECK-NEXT: movne 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: mvn r1, #0 ; CHECK-NEXT: tst r0, #1 ; CHECK-NEXT: movne r1, #0 ; CHECK-NEXT: mov r0, r1 ; 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: mvn r1, #0 ; CHECK-NEXT: cmp r0, #0 ; CHECK-NEXT: movne r1, #0 ; CHECK-NEXT: mov r0, r1 ; 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 r1, #0 ; CHECK-NEXT: tst r0, #1 ; CHECK-NEXT: movne r1, #0 ; CHECK-NEXT: mov r0, r1 ; CHECK-NEXT: mov pc, lr %sel = select i1 %cond, i32 0, i32 -1 ret i32 %sel } ; 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: ands r0, r0, #1 ; CHECK-NEXT: mvnne 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: cmp r0, #0 ; CHECK-NEXT: mvnne 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: ands r0, r0, #1 ; CHECK-NEXT: mvnne r0, #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 }