157 lines · plain
1; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py2; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=-bmi2,-lzcnt | FileCheck %s --check-prefix=NOBMI3; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+bmi2,+lzcnt | FileCheck %s --check-prefix=BMI4 5; Check the assembly sequence generated for std::bit_ceil.6 7; std::bit_ceil<uint32_t>(x)8define i32 @bit_ceil_i32(i32 %x) {9; NOBMI-LABEL: bit_ceil_i32:10; NOBMI: # %bb.0:11; NOBMI-NEXT: # kill: def $edi killed $edi def $rdi12; NOBMI-NEXT: leal -1(%rdi), %eax13; NOBMI-NEXT: movl $63, %ecx14; NOBMI-NEXT: bsrl %eax, %ecx15; NOBMI-NEXT: xorl $31, %ecx16; NOBMI-NEXT: negb %cl17; NOBMI-NEXT: movl $1, %edx18; NOBMI-NEXT: movl $1, %eax19; NOBMI-NEXT: # kill: def $cl killed $cl killed $ecx20; NOBMI-NEXT: shll %cl, %eax21; NOBMI-NEXT: cmpl $2, %edi22; NOBMI-NEXT: cmovbl %edx, %eax23; NOBMI-NEXT: retq24;25; BMI-LABEL: bit_ceil_i32:26; BMI: # %bb.0:27; BMI-NEXT: # kill: def $edi killed $edi def $rdi28; BMI-NEXT: leal -1(%rdi), %eax29; BMI-NEXT: lzcntl %eax, %eax30; BMI-NEXT: negb %al31; BMI-NEXT: movl $1, %ecx32; BMI-NEXT: shlxl %eax, %ecx, %eax33; BMI-NEXT: cmpl $2, %edi34; BMI-NEXT: cmovbl %ecx, %eax35; BMI-NEXT: retq36 %dec = add i32 %x, -137 %lz = tail call i32 @llvm.ctlz.i32(i32 %dec, i1 false)38 %cnt = sub i32 32, %lz39 %res = shl i32 1, %cnt40 %ugt = icmp ugt i32 %x, 141 %sel = select i1 %ugt, i32 %res, i32 142 ret i32 %sel43}44 45; std::bit_ceil<uint32_t>(x + 1)46define i32 @bit_ceil_i32_plus1(i32 noundef %x) {47; NOBMI-LABEL: bit_ceil_i32_plus1:48; NOBMI: # %bb.0: # %entry49; NOBMI-NEXT: movl $63, %ecx50; NOBMI-NEXT: bsrl %edi, %ecx51; NOBMI-NEXT: xorl $31, %ecx52; NOBMI-NEXT: negb %cl53; NOBMI-NEXT: movl $1, %edx54; NOBMI-NEXT: movl $1, %eax55; NOBMI-NEXT: # kill: def $cl killed $cl killed $ecx56; NOBMI-NEXT: shll %cl, %eax57; NOBMI-NEXT: decl %edi58; NOBMI-NEXT: cmpl $-2, %edi59; NOBMI-NEXT: cmovael %edx, %eax60; NOBMI-NEXT: retq61;62; BMI-LABEL: bit_ceil_i32_plus1:63; BMI: # %bb.0: # %entry64; BMI-NEXT: lzcntl %edi, %eax65; BMI-NEXT: negb %al66; BMI-NEXT: movl $1, %ecx67; BMI-NEXT: shlxl %eax, %ecx, %eax68; BMI-NEXT: decl %edi69; BMI-NEXT: cmpl $-2, %edi70; BMI-NEXT: cmovael %ecx, %eax71; BMI-NEXT: retq72entry:73 %ctlz = tail call i32 @llvm.ctlz.i32(i32 %x, i1 false)74 %cnt = sub i32 32, %ctlz75 %shl = shl i32 1, %cnt76 %dec = add i32 %x, -177 %ult = icmp ult i32 %dec, -278 %sel = select i1 %ult, i32 %shl, i32 179 ret i32 %sel80}81 82; std::bit_ceil<uint64_t>(x)83define i64 @bit_ceil_i64(i64 %x) {84; NOBMI-LABEL: bit_ceil_i64:85; NOBMI: # %bb.0:86; NOBMI-NEXT: leaq -1(%rdi), %rax87; NOBMI-NEXT: movl $127, %ecx88; NOBMI-NEXT: bsrq %rax, %rcx89; NOBMI-NEXT: xorl $63, %ecx90; NOBMI-NEXT: negb %cl91; NOBMI-NEXT: movl $1, %edx92; NOBMI-NEXT: movl $1, %eax93; NOBMI-NEXT: # kill: def $cl killed $cl killed $rcx94; NOBMI-NEXT: shlq %cl, %rax95; NOBMI-NEXT: cmpq $2, %rdi96; NOBMI-NEXT: cmovbq %rdx, %rax97; NOBMI-NEXT: retq98;99; BMI-LABEL: bit_ceil_i64:100; BMI: # %bb.0:101; BMI-NEXT: leaq -1(%rdi), %rax102; BMI-NEXT: lzcntq %rax, %rax103; BMI-NEXT: negb %al104; BMI-NEXT: movl $1, %ecx105; BMI-NEXT: shlxq %rax, %rcx, %rax106; BMI-NEXT: cmpq $2, %rdi107; BMI-NEXT: cmovbq %rcx, %rax108; BMI-NEXT: retq109 %dec = add i64 %x, -1110 %lz = tail call i64 @llvm.ctlz.i64(i64 %dec, i1 false)111 %cnt = sub i64 64, %lz112 %res = shl i64 1, %cnt113 %ugt = icmp ugt i64 %x, 1114 %sel = select i1 %ugt, i64 %res, i64 1115 ret i64 %sel116}117 118; std::bit_ceil<uint64_t>(x + 1)119define i64 @bit_ceil_i64_plus1(i64 noundef %x) {120; NOBMI-LABEL: bit_ceil_i64_plus1:121; NOBMI: # %bb.0: # %entry122; NOBMI-NEXT: movl $127, %ecx123; NOBMI-NEXT: bsrq %rdi, %rcx124; NOBMI-NEXT: xorl $63, %ecx125; NOBMI-NEXT: negb %cl126; NOBMI-NEXT: movl $1, %edx127; NOBMI-NEXT: movl $1, %eax128; NOBMI-NEXT: # kill: def $cl killed $cl killed $rcx129; NOBMI-NEXT: shlq %cl, %rax130; NOBMI-NEXT: decq %rdi131; NOBMI-NEXT: cmpq $-2, %rdi132; NOBMI-NEXT: cmovaeq %rdx, %rax133; NOBMI-NEXT: retq134;135; BMI-LABEL: bit_ceil_i64_plus1:136; BMI: # %bb.0: # %entry137; BMI-NEXT: lzcntq %rdi, %rax138; BMI-NEXT: negb %al139; BMI-NEXT: movl $1, %ecx140; BMI-NEXT: shlxq %rax, %rcx, %rax141; BMI-NEXT: decq %rdi142; BMI-NEXT: cmpq $-2, %rdi143; BMI-NEXT: cmovaeq %rcx, %rax144; BMI-NEXT: retq145entry:146 %ctlz = tail call i64 @llvm.ctlz.i64(i64 %x, i1 false)147 %cnt = sub i64 64, %ctlz148 %shl = shl i64 1, %cnt149 %dec = add i64 %x, -1150 %ult = icmp ult i64 %dec, -2151 %sel = select i1 %ult, i64 %shl, i64 1152 ret i64 %sel153}154 155declare i32 @llvm.ctlz.i32(i32, i1 immarg)156declare i64 @llvm.ctlz.i64(i64, i1 immarg)157