; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6 ; RUN: llc -mtriple=x86_64-unknown-unknown < %s | FileCheck %s ; ; Verify that ADD(SBB(Y,0,flags),C) folds to SBB(Y,-C,flags). ; SBB(Y,0) = Y - CF; adding C gives Y - CF + C = Y - (-C) - CF = SBB(Y,-C). ; ; Fold should fire because all conditions are met define i64 @g_i64(i64 %a, i64 %b) { ; CHECK-LABEL: g_i64: ; CHECK: # %bb.0: ; CHECK-NEXT: movq %rdi, %rax ; CHECK-NEXT: subq %rsi, %rax ; CHECK-NEXT: sbbq $-10, %rax ; CHECK-NEXT: retq %ov = call {i64, i1} @llvm.usub.with.overflow.i64(i64 %a, i64 %b) %val = extractvalue { i64, i1 } %ov, 0 %bit = extractvalue { i64, i1 } %ov, 1 %ext = sext i1 %bit to i64 %r = add i64 %val, %ext %r2 = add i64 %r, 10 ret i64 %r2 } ; Fold should fire because all conditions are met define i32 @g_i32(i32 %a, i32 %b) { ; CHECK-LABEL: g_i32: ; CHECK: # %bb.0: ; CHECK-NEXT: movl %edi, %eax ; CHECK-NEXT: subl %esi, %eax ; CHECK-NEXT: sbbl $-10, %eax ; CHECK-NEXT: retq %ov = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 %b) %val = extractvalue { i32, i1 } %ov, 0 %bit = extractvalue { i32, i1 } %ov, 1 %ext = sext i1 %bit to i32 %r = add i32 %val, %ext %r2 = add i32 %r, 10 ret i32 %r2 } ; Non-constant addend, fold should still fire. define i64 @g_nonconstant(i64 %a, i64 %b, i64 %c) { ; CHECK-LABEL: g_nonconstant: ; CHECK: # %bb.0: ; CHECK-NEXT: movq %rdi, %rax ; CHECK-NEXT: negq %rdx ; CHECK-NEXT: subq %rsi, %rax ; CHECK-NEXT: sbbq %rdx, %rax ; CHECK-NEXT: retq %ov = call {i64, i1} @llvm.usub.with.overflow.i64(i64 %a, i64 %b) %val = extractvalue { i64, i1 } %ov, 0 %bit = extractvalue { i64, i1 } %ov, 1 %ext = sext i1 %bit to i64 %r = add i64 %val, %ext %r2 = add i64 %r, %c ret i64 %r2 } ; Non-constant addend, fold should still fire. define i32 @g_nonconstant_i32(i32 %a, i32 %b, i32 %c) { ; CHECK-LABEL: g_nonconstant_i32: ; CHECK: # %bb.0: ; CHECK-NEXT: movl %edi, %eax ; CHECK-NEXT: negl %edx ; CHECK-NEXT: subl %esi, %eax ; CHECK-NEXT: sbbl %edx, %eax ; CHECK-NEXT: retq %ov = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 %b) %val = extractvalue { i32, i1 } %ov, 0 %bit = extractvalue { i32, i1 } %ov, 1 %ext = sext i1 %bit to i32 %r = add i32 %val, %ext %r2 = add i32 %r, %c ret i32 %r2 } ; Non-constant addend in commuted form, fold should still fire. define i64 @g_nonconstant_commuted(i64 %a, i64 %b, i64 %c) { ; CHECK-LABEL: g_nonconstant_commuted: ; CHECK: # %bb.0: ; CHECK-NEXT: movq %rdi, %rax ; CHECK-NEXT: negq %rdx ; CHECK-NEXT: subq %rsi, %rax ; CHECK-NEXT: sbbq %rdx, %rax ; CHECK-NEXT: retq %ov = call {i64, i1} @llvm.usub.with.overflow.i64(i64 %a, i64 %b) %val = extractvalue { i64, i1 } %ov, 0 %bit = extractvalue { i64, i1 } %ov, 1 %ext = sext i1 %bit to i64 %r = add i64 %val, %ext %r2 = add i64 %c, %r ret i64 %r2 } ; Non-constant addend in commuted form, fold should still fire. define i32 @g_nonconstant_commuted_i32(i32 %a, i32 %b, i32 %c) { ; CHECK-LABEL: g_nonconstant_commuted_i32: ; CHECK: # %bb.0: ; CHECK-NEXT: movl %edi, %eax ; CHECK-NEXT: negl %edx ; CHECK-NEXT: subl %esi, %eax ; CHECK-NEXT: sbbl %edx, %eax ; CHECK-NEXT: retq %ov = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 %b) %val = extractvalue { i32, i1 } %ov, 0 %bit = extractvalue { i32, i1 } %ov, 1 %ext = sext i1 %bit to i32 %r = add i32 %val, %ext %r2 = add i32 %c, %r ret i32 %r2 } ; INT_MIN should fold correctly too. define i32 @g_i32_int_min(i32 %a, i32 %b) { ; CHECK-LABEL: g_i32_int_min: ; CHECK: # %bb.0: ; CHECK-NEXT: movl %edi, %eax ; CHECK-NEXT: subl %esi, %eax ; CHECK-NEXT: sbbl $-2147483648, %eax # imm = 0x80000000 ; CHECK-NEXT: retq %ov = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 %b) %val = extractvalue { i32, i1 } %ov, 0 %bit = extractvalue { i32, i1 } %ov, 1 %ext = sext i1 %bit to i32 %r = add i32 %val, %ext %r2 = add i32 %r, -2147483648 ret i32 %r2 } ; Multiple uses of SBB result, fold should not fire define i64 @g_multi_use(i64 %a, i64 %b, ptr %out) { ; CHECK-LABEL: g_multi_use: ; CHECK: # %bb.0: ; CHECK-NEXT: subq %rsi, %rdi ; CHECK-NEXT: sbbq $0, %rdi ; CHECK-NEXT: movq %rdi, (%rdx) ; CHECK-NEXT: leaq 10(%rdi), %rax ; CHECK-NEXT: retq %ov = call {i64, i1} @llvm.usub.with.overflow.i64(i64 %a, i64 %b) %val = extractvalue { i64, i1 } %ov, 0 %bit = extractvalue { i64, i1 } %ov, 1 %ext = sext i1 %bit to i64 %sbb = add i64 %val, %ext store i64 %sbb, ptr %out %r = add i64 %sbb, 10 ret i64 %r } ; Multiple uses of SBB result, fold should not fire define i32 @g_multi_use_i32(i32 %a, i32 %b, ptr %out) { ; CHECK-LABEL: g_multi_use_i32: ; CHECK: # %bb.0: ; CHECK-NEXT: # kill: def $edi killed $edi def $rdi ; CHECK-NEXT: subl %esi, %edi ; CHECK-NEXT: sbbl $0, %edi ; CHECK-NEXT: movl %edi, (%rdx) ; CHECK-NEXT: leal 10(%rdi), %eax ; CHECK-NEXT: retq %ov = call {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 %b) %val = extractvalue { i32, i1 } %ov, 0 %bit = extractvalue { i32, i1 } %ov, 1 %ext = sext i1 %bit to i32 %sbb = add i32 %val, %ext store i32 %sbb, ptr %out %r = add i32 %sbb, 10 ret i32 %r } ; Flags live across the low-limb constant add into the next SBB in the chain. ; Fold should not fire. define {i64, i64} @g_flags_live(i64 %a_lo, i64 %a_hi, i64 %b_lo, i64 %b_hi) { ; CHECK-LABEL: g_flags_live: ; CHECK: # %bb.0: ; CHECK-NEXT: subq %rdx, %rdi ; CHECK-NEXT: leaq 10(%rdi), %rax ; CHECK-NEXT: sbbq %rcx, %rsi ; CHECK-NEXT: movq %rsi, %rdx ; CHECK-NEXT: retq %lo = call { i8, i64 } @llvm.x86.subborrow.64(i8 0, i64 %a_lo, i64 %b_lo) %lo_b = extractvalue { i8, i64 } %lo, 0 %lo_val = extractvalue { i8, i64 } %lo, 1 %lo_plus = add i64 %lo_val, 10 %hi = call { i8, i64 } @llvm.x86.subborrow.64(i8 %lo_b, i64 %a_hi, i64 %b_hi) %hi_val = extractvalue { i8, i64 } %hi, 1 %ret = insertvalue {i64, i64} poison, i64 %lo_plus, 0 %ret2 = insertvalue {i64, i64} %ret, i64 %hi_val, 1 ret {i64, i64} %ret2 }