; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py ; RUN: llc < %s -mtriple=i686-unknown-unknown | FileCheck %s --check-prefixes=X86,X86-NOCMOV ; RUN: llc < %s -mtriple=i686-unknown-unknown -mattr=+cmov | FileCheck %s --check-prefixes=X86,X86-CMOV ; RUN: llc < %s -mtriple=x86_64-unknown-unknown | FileCheck %s --check-prefix=X64 ; RUN: llc < %s -mtriple=i686-unknown-unknown -mattr=+bmi,+lzcnt | FileCheck %s --check-prefix=X86-CLZ ; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+bmi,+lzcnt | FileCheck %s --check-prefix=X64-CLZ declare i8 @llvm.cttz.i8(i8, i1) declare i16 @llvm.cttz.i16(i16, i1) declare i32 @llvm.cttz.i32(i32, i1) declare i64 @llvm.cttz.i64(i64, i1) declare i8 @llvm.ctlz.i8(i8, i1) declare i16 @llvm.ctlz.i16(i16, i1) declare i32 @llvm.ctlz.i32(i32, i1) declare i64 @llvm.ctlz.i64(i64, i1) define i8 @cttz_i8(i8 %x) { ; X86-LABEL: cttz_i8: ; X86: # %bb.0: ; X86-NEXT: bsfl {{[0-9]+}}(%esp), %eax ; X86-NEXT: # kill: def $al killed $al killed $eax ; X86-NEXT: retl ; ; X64-LABEL: cttz_i8: ; X64: # %bb.0: ; X64-NEXT: bsfl %edi, %eax ; X64-NEXT: # kill: def $al killed $al killed $eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: cttz_i8: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: tzcntl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: # kill: def $al killed $al killed $eax ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: cttz_i8: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: tzcntl %edi, %eax ; X64-CLZ-NEXT: # kill: def $al killed $al killed $eax ; X64-CLZ-NEXT: retq %tmp = call i8 @llvm.cttz.i8( i8 %x, i1 true ) ret i8 %tmp } define i16 @cttz_i16(i16 %x) { ; X86-LABEL: cttz_i16: ; X86: # %bb.0: ; X86-NEXT: bsfw {{[0-9]+}}(%esp), %ax ; X86-NEXT: retl ; ; X64-LABEL: cttz_i16: ; X64: # %bb.0: ; X64-NEXT: bsfw %di, %ax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: cttz_i16: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: tzcntw {{[0-9]+}}(%esp), %ax ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: cttz_i16: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: tzcntw %di, %ax ; X64-CLZ-NEXT: retq %tmp = call i16 @llvm.cttz.i16( i16 %x, i1 true ) ret i16 %tmp } define i32 @cttz_i32(i32 %x) { ; X86-LABEL: cttz_i32: ; X86: # %bb.0: ; X86-NEXT: bsfl {{[0-9]+}}(%esp), %eax ; X86-NEXT: retl ; ; X64-LABEL: cttz_i32: ; X64: # %bb.0: ; X64-NEXT: bsfl %edi, %eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: cttz_i32: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: tzcntl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: cttz_i32: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: tzcntl %edi, %eax ; X64-CLZ-NEXT: retq %tmp = call i32 @llvm.cttz.i32( i32 %x, i1 true ) ret i32 %tmp } define i64 @cttz_i64(i64 %x) { ; X86-NOCMOV-LABEL: cttz_i64: ; X86-NOCMOV: # %bb.0: ; X86-NOCMOV-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-NOCMOV-NEXT: testl %eax, %eax ; X86-NOCMOV-NEXT: jne .LBB3_1 ; X86-NOCMOV-NEXT: # %bb.2: ; X86-NOCMOV-NEXT: bsfl {{[0-9]+}}(%esp), %eax ; X86-NOCMOV-NEXT: addl $32, %eax ; X86-NOCMOV-NEXT: xorl %edx, %edx ; X86-NOCMOV-NEXT: retl ; X86-NOCMOV-NEXT: .LBB3_1: ; X86-NOCMOV-NEXT: bsfl %eax, %eax ; X86-NOCMOV-NEXT: xorl %edx, %edx ; X86-NOCMOV-NEXT: retl ; ; X86-CMOV-LABEL: cttz_i64: ; X86-CMOV: # %bb.0: ; X86-CMOV-NEXT: movl {{[0-9]+}}(%esp), %ecx ; X86-CMOV-NEXT: bsfl %ecx, %edx ; X86-CMOV-NEXT: bsfl {{[0-9]+}}(%esp), %eax ; X86-CMOV-NEXT: addl $32, %eax ; X86-CMOV-NEXT: testl %ecx, %ecx ; X86-CMOV-NEXT: cmovnel %edx, %eax ; X86-CMOV-NEXT: xorl %edx, %edx ; X86-CMOV-NEXT: retl ; ; X64-LABEL: cttz_i64: ; X64: # %bb.0: ; X64-NEXT: bsfq %rdi, %rax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: cttz_i64: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: testl %eax, %eax ; X86-CLZ-NEXT: jne .LBB3_1 ; X86-CLZ-NEXT: # %bb.2: ; X86-CLZ-NEXT: tzcntl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: addl $32, %eax ; X86-CLZ-NEXT: xorl %edx, %edx ; X86-CLZ-NEXT: retl ; X86-CLZ-NEXT: .LBB3_1: ; X86-CLZ-NEXT: tzcntl %eax, %eax ; X86-CLZ-NEXT: xorl %edx, %edx ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: cttz_i64: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: tzcntq %rdi, %rax ; X64-CLZ-NEXT: retq %tmp = call i64 @llvm.cttz.i64( i64 %x, i1 true ) ret i64 %tmp } define i8 @ctlz_i8(i8 %x) { ; X86-LABEL: ctlz_i8: ; X86: # %bb.0: ; X86-NEXT: movzbl {{[0-9]+}}(%esp), %eax ; X86-NEXT: bsrl %eax, %eax ; X86-NEXT: xorl $7, %eax ; X86-NEXT: # kill: def $al killed $al killed $eax ; X86-NEXT: retl ; ; X64-LABEL: ctlz_i8: ; X64: # %bb.0: ; X64-NEXT: movzbl %dil, %eax ; X64-NEXT: bsrl %eax, %eax ; X64-NEXT: xorl $7, %eax ; X64-NEXT: # kill: def $al killed $al killed $eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: ctlz_i8: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: movzbl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: lzcntl %eax, %eax ; X86-CLZ-NEXT: addl $-24, %eax ; X86-CLZ-NEXT: # kill: def $al killed $al killed $eax ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: ctlz_i8: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: movzbl %dil, %eax ; X64-CLZ-NEXT: lzcntl %eax, %eax ; X64-CLZ-NEXT: addl $-24, %eax ; X64-CLZ-NEXT: # kill: def $al killed $al killed $eax ; X64-CLZ-NEXT: retq %tmp2 = call i8 @llvm.ctlz.i8( i8 %x, i1 true ) ret i8 %tmp2 } define i16 @ctlz_i16(i16 %x) { ; X86-LABEL: ctlz_i16: ; X86: # %bb.0: ; X86-NEXT: bsrw {{[0-9]+}}(%esp), %ax ; X86-NEXT: xorl $15, %eax ; X86-NEXT: # kill: def $ax killed $ax killed $eax ; X86-NEXT: retl ; ; X64-LABEL: ctlz_i16: ; X64: # %bb.0: ; X64-NEXT: bsrw %di, %ax ; X64-NEXT: xorl $15, %eax ; X64-NEXT: # kill: def $ax killed $ax killed $eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: ctlz_i16: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: lzcntw {{[0-9]+}}(%esp), %ax ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: ctlz_i16: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: lzcntw %di, %ax ; X64-CLZ-NEXT: retq %tmp2 = call i16 @llvm.ctlz.i16( i16 %x, i1 true ) ret i16 %tmp2 } define i32 @ctlz_i32(i32 %x) { ; X86-LABEL: ctlz_i32: ; X86: # %bb.0: ; X86-NEXT: bsrl {{[0-9]+}}(%esp), %eax ; X86-NEXT: xorl $31, %eax ; X86-NEXT: retl ; ; X64-LABEL: ctlz_i32: ; X64: # %bb.0: ; X64-NEXT: bsrl %edi, %eax ; X64-NEXT: xorl $31, %eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: ctlz_i32: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: lzcntl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: ctlz_i32: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: lzcntl %edi, %eax ; X64-CLZ-NEXT: retq %tmp = call i32 @llvm.ctlz.i32( i32 %x, i1 true ) ret i32 %tmp } define i64 @ctlz_i64(i64 %x) { ; X86-NOCMOV-LABEL: ctlz_i64: ; X86-NOCMOV: # %bb.0: ; X86-NOCMOV-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-NOCMOV-NEXT: testl %eax, %eax ; X86-NOCMOV-NEXT: jne .LBB7_1 ; X86-NOCMOV-NEXT: # %bb.2: ; X86-NOCMOV-NEXT: bsrl {{[0-9]+}}(%esp), %eax ; X86-NOCMOV-NEXT: xorl $31, %eax ; X86-NOCMOV-NEXT: addl $32, %eax ; X86-NOCMOV-NEXT: xorl %edx, %edx ; X86-NOCMOV-NEXT: retl ; X86-NOCMOV-NEXT: .LBB7_1: ; X86-NOCMOV-NEXT: bsrl %eax, %eax ; X86-NOCMOV-NEXT: xorl $31, %eax ; X86-NOCMOV-NEXT: xorl %edx, %edx ; X86-NOCMOV-NEXT: retl ; ; X86-CMOV-LABEL: ctlz_i64: ; X86-CMOV: # %bb.0: ; X86-CMOV-NEXT: movl {{[0-9]+}}(%esp), %ecx ; X86-CMOV-NEXT: bsrl %ecx, %edx ; X86-CMOV-NEXT: xorl $31, %edx ; X86-CMOV-NEXT: bsrl {{[0-9]+}}(%esp), %eax ; X86-CMOV-NEXT: xorl $31, %eax ; X86-CMOV-NEXT: addl $32, %eax ; X86-CMOV-NEXT: testl %ecx, %ecx ; X86-CMOV-NEXT: cmovnel %edx, %eax ; X86-CMOV-NEXT: xorl %edx, %edx ; X86-CMOV-NEXT: retl ; ; X64-LABEL: ctlz_i64: ; X64: # %bb.0: ; X64-NEXT: bsrq %rdi, %rax ; X64-NEXT: xorq $63, %rax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: ctlz_i64: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: testl %eax, %eax ; X86-CLZ-NEXT: jne .LBB7_1 ; X86-CLZ-NEXT: # %bb.2: ; X86-CLZ-NEXT: lzcntl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: addl $32, %eax ; X86-CLZ-NEXT: xorl %edx, %edx ; X86-CLZ-NEXT: retl ; X86-CLZ-NEXT: .LBB7_1: ; X86-CLZ-NEXT: lzcntl %eax, %eax ; X86-CLZ-NEXT: xorl %edx, %edx ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: ctlz_i64: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: lzcntq %rdi, %rax ; X64-CLZ-NEXT: retq %tmp = call i64 @llvm.ctlz.i64( i64 %x, i1 true ) ret i64 %tmp } ; Generate a test and branch to handle zero inputs because bsr/bsf are very slow. define i8 @ctlz_i8_zero_test(i8 %n) { ; X86-LABEL: ctlz_i8_zero_test: ; X86: # %bb.0: ; X86-NEXT: movb {{[0-9]+}}(%esp), %al ; X86-NEXT: testb %al, %al ; X86-NEXT: je .LBB8_1 ; X86-NEXT: # %bb.2: # %cond.false ; X86-NEXT: movzbl %al, %eax ; X86-NEXT: bsrl %eax, %eax ; X86-NEXT: xorl $7, %eax ; X86-NEXT: # kill: def $al killed $al killed $eax ; X86-NEXT: retl ; X86-NEXT: .LBB8_1: ; X86-NEXT: movb $8, %al ; X86-NEXT: # kill: def $al killed $al killed $eax ; X86-NEXT: retl ; ; X64-LABEL: ctlz_i8_zero_test: ; X64: # %bb.0: ; X64-NEXT: testb %dil, %dil ; X64-NEXT: je .LBB8_1 ; X64-NEXT: # %bb.2: # %cond.false ; X64-NEXT: movzbl %dil, %eax ; X64-NEXT: bsrl %eax, %eax ; X64-NEXT: xorl $7, %eax ; X64-NEXT: # kill: def $al killed $al killed $eax ; X64-NEXT: retq ; X64-NEXT: .LBB8_1: ; X64-NEXT: movb $8, %al ; X64-NEXT: # kill: def $al killed $al killed $eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: ctlz_i8_zero_test: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: movzbl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: lzcntl %eax, %eax ; X86-CLZ-NEXT: addl $-24, %eax ; X86-CLZ-NEXT: # kill: def $al killed $al killed $eax ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: ctlz_i8_zero_test: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: movzbl %dil, %eax ; X64-CLZ-NEXT: lzcntl %eax, %eax ; X64-CLZ-NEXT: addl $-24, %eax ; X64-CLZ-NEXT: # kill: def $al killed $al killed $eax ; X64-CLZ-NEXT: retq %tmp1 = call i8 @llvm.ctlz.i8(i8 %n, i1 false) ret i8 %tmp1 } ; Generate a test and branch to handle zero inputs because bsr/bsf are very slow. define i16 @ctlz_i16_zero_test(i16 %n) { ; X86-LABEL: ctlz_i16_zero_test: ; X86: # %bb.0: ; X86-NEXT: movzwl {{[0-9]+}}(%esp), %eax ; X86-NEXT: testw %ax, %ax ; X86-NEXT: je .LBB9_1 ; X86-NEXT: # %bb.2: # %cond.false ; X86-NEXT: bsrw %ax, %ax ; X86-NEXT: xorl $15, %eax ; X86-NEXT: # kill: def $ax killed $ax killed $eax ; X86-NEXT: retl ; X86-NEXT: .LBB9_1: ; X86-NEXT: movw $16, %ax ; X86-NEXT: # kill: def $ax killed $ax killed $eax ; X86-NEXT: retl ; ; X64-LABEL: ctlz_i16_zero_test: ; X64: # %bb.0: ; X64-NEXT: testw %di, %di ; X64-NEXT: je .LBB9_1 ; X64-NEXT: # %bb.2: # %cond.false ; X64-NEXT: bsrw %di, %ax ; X64-NEXT: xorl $15, %eax ; X64-NEXT: # kill: def $ax killed $ax killed $eax ; X64-NEXT: retq ; X64-NEXT: .LBB9_1: ; X64-NEXT: movw $16, %ax ; X64-NEXT: # kill: def $ax killed $ax killed $eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: ctlz_i16_zero_test: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: lzcntw {{[0-9]+}}(%esp), %ax ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: ctlz_i16_zero_test: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: lzcntw %di, %ax ; X64-CLZ-NEXT: retq %tmp1 = call i16 @llvm.ctlz.i16(i16 %n, i1 false) ret i16 %tmp1 } ; Generate a test and branch to handle zero inputs because bsr/bsf are very slow. define i32 @ctlz_i32_zero_test(i32 %n) { ; X86-LABEL: ctlz_i32_zero_test: ; X86: # %bb.0: ; X86-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-NEXT: testl %eax, %eax ; X86-NEXT: je .LBB10_1 ; X86-NEXT: # %bb.2: # %cond.false ; X86-NEXT: bsrl %eax, %eax ; X86-NEXT: xorl $31, %eax ; X86-NEXT: retl ; X86-NEXT: .LBB10_1: ; X86-NEXT: movl $32, %eax ; X86-NEXT: retl ; ; X64-LABEL: ctlz_i32_zero_test: ; X64: # %bb.0: ; X64-NEXT: testl %edi, %edi ; X64-NEXT: je .LBB10_1 ; X64-NEXT: # %bb.2: # %cond.false ; X64-NEXT: bsrl %edi, %eax ; X64-NEXT: xorl $31, %eax ; X64-NEXT: retq ; X64-NEXT: .LBB10_1: ; X64-NEXT: movl $32, %eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: ctlz_i32_zero_test: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: lzcntl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: ctlz_i32_zero_test: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: lzcntl %edi, %eax ; X64-CLZ-NEXT: retq %tmp1 = call i32 @llvm.ctlz.i32(i32 %n, i1 false) ret i32 %tmp1 } ; Generate a test and branch to handle zero inputs because bsr/bsf are very slow. define i64 @ctlz_i64_zero_test(i64 %n) { ; X86-NOCMOV-LABEL: ctlz_i64_zero_test: ; X86-NOCMOV: # %bb.0: ; X86-NOCMOV-NEXT: movl {{[0-9]+}}(%esp), %ecx ; X86-NOCMOV-NEXT: bsrl {{[0-9]+}}(%esp), %edx ; X86-NOCMOV-NEXT: movl $63, %eax ; X86-NOCMOV-NEXT: je .LBB11_2 ; X86-NOCMOV-NEXT: # %bb.1: ; X86-NOCMOV-NEXT: movl %edx, %eax ; X86-NOCMOV-NEXT: .LBB11_2: ; X86-NOCMOV-NEXT: testl %ecx, %ecx ; X86-NOCMOV-NEXT: jne .LBB11_3 ; X86-NOCMOV-NEXT: # %bb.4: ; X86-NOCMOV-NEXT: xorl $31, %eax ; X86-NOCMOV-NEXT: addl $32, %eax ; X86-NOCMOV-NEXT: xorl %edx, %edx ; X86-NOCMOV-NEXT: retl ; X86-NOCMOV-NEXT: .LBB11_3: ; X86-NOCMOV-NEXT: bsrl %ecx, %eax ; X86-NOCMOV-NEXT: xorl $31, %eax ; X86-NOCMOV-NEXT: xorl %edx, %edx ; X86-NOCMOV-NEXT: retl ; ; X86-CMOV-LABEL: ctlz_i64_zero_test: ; X86-CMOV: # %bb.0: ; X86-CMOV-NEXT: movl {{[0-9]+}}(%esp), %ecx ; X86-CMOV-NEXT: bsrl {{[0-9]+}}(%esp), %eax ; X86-CMOV-NEXT: movl $63, %edx ; X86-CMOV-NEXT: cmovnel %eax, %edx ; X86-CMOV-NEXT: xorl $31, %edx ; X86-CMOV-NEXT: addl $32, %edx ; X86-CMOV-NEXT: bsrl %ecx, %eax ; X86-CMOV-NEXT: xorl $31, %eax ; X86-CMOV-NEXT: testl %ecx, %ecx ; X86-CMOV-NEXT: cmovel %edx, %eax ; X86-CMOV-NEXT: xorl %edx, %edx ; X86-CMOV-NEXT: retl ; ; X64-LABEL: ctlz_i64_zero_test: ; X64: # %bb.0: ; X64-NEXT: testq %rdi, %rdi ; X64-NEXT: je .LBB11_1 ; X64-NEXT: # %bb.2: # %cond.false ; X64-NEXT: bsrq %rdi, %rax ; X64-NEXT: xorq $63, %rax ; X64-NEXT: retq ; X64-NEXT: .LBB11_1: ; X64-NEXT: movl $64, %eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: ctlz_i64_zero_test: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: testl %eax, %eax ; X86-CLZ-NEXT: jne .LBB11_1 ; X86-CLZ-NEXT: # %bb.2: ; X86-CLZ-NEXT: lzcntl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: addl $32, %eax ; X86-CLZ-NEXT: xorl %edx, %edx ; X86-CLZ-NEXT: retl ; X86-CLZ-NEXT: .LBB11_1: ; X86-CLZ-NEXT: lzcntl %eax, %eax ; X86-CLZ-NEXT: xorl %edx, %edx ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: ctlz_i64_zero_test: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: lzcntq %rdi, %rax ; X64-CLZ-NEXT: retq %tmp1 = call i64 @llvm.ctlz.i64(i64 %n, i1 false) ret i64 %tmp1 } ; Generate a test and branch to handle zero inputs because bsr/bsf are very slow. define i8 @cttz_i8_zero_test(i8 %n) { ; X86-LABEL: cttz_i8_zero_test: ; X86: # %bb.0: ; X86-NEXT: movb {{[0-9]+}}(%esp), %al ; X86-NEXT: testb %al, %al ; X86-NEXT: je .LBB12_1 ; X86-NEXT: # %bb.2: # %cond.false ; X86-NEXT: movzbl %al, %eax ; X86-NEXT: bsfl %eax, %eax ; X86-NEXT: # kill: def $al killed $al killed $eax ; X86-NEXT: retl ; X86-NEXT: .LBB12_1: ; X86-NEXT: movb $8, %al ; X86-NEXT: # kill: def $al killed $al killed $eax ; X86-NEXT: retl ; ; X64-LABEL: cttz_i8_zero_test: ; X64: # %bb.0: ; X64-NEXT: testb %dil, %dil ; X64-NEXT: je .LBB12_1 ; X64-NEXT: # %bb.2: # %cond.false ; X64-NEXT: movzbl %dil, %eax ; X64-NEXT: bsfl %eax, %eax ; X64-NEXT: # kill: def $al killed $al killed $eax ; X64-NEXT: retq ; X64-NEXT: .LBB12_1: ; X64-NEXT: movb $8, %al ; X64-NEXT: # kill: def $al killed $al killed $eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: cttz_i8_zero_test: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: movl $256, %eax # imm = 0x100 ; X86-CLZ-NEXT: orl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: tzcntl %eax, %eax ; X86-CLZ-NEXT: # kill: def $al killed $al killed $eax ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: cttz_i8_zero_test: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: orl $256, %edi # imm = 0x100 ; X64-CLZ-NEXT: tzcntl %edi, %eax ; X64-CLZ-NEXT: # kill: def $al killed $al killed $eax ; X64-CLZ-NEXT: retq %tmp1 = call i8 @llvm.cttz.i8(i8 %n, i1 false) ret i8 %tmp1 } ; Generate a test and branch to handle zero inputs because bsr/bsf are very slow. define i16 @cttz_i16_zero_test(i16 %n) { ; X86-LABEL: cttz_i16_zero_test: ; X86: # %bb.0: ; X86-NEXT: movzwl {{[0-9]+}}(%esp), %eax ; X86-NEXT: testw %ax, %ax ; X86-NEXT: je .LBB13_1 ; X86-NEXT: # %bb.2: # %cond.false ; X86-NEXT: bsfw %ax, %ax ; X86-NEXT: retl ; X86-NEXT: .LBB13_1: ; X86-NEXT: movw $16, %ax ; X86-NEXT: retl ; ; X64-LABEL: cttz_i16_zero_test: ; X64: # %bb.0: ; X64-NEXT: testw %di, %di ; X64-NEXT: je .LBB13_1 ; X64-NEXT: # %bb.2: # %cond.false ; X64-NEXT: bsfw %di, %ax ; X64-NEXT: retq ; X64-NEXT: .LBB13_1: ; X64-NEXT: movw $16, %ax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: cttz_i16_zero_test: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: tzcntw {{[0-9]+}}(%esp), %ax ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: cttz_i16_zero_test: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: tzcntw %di, %ax ; X64-CLZ-NEXT: retq %tmp1 = call i16 @llvm.cttz.i16(i16 %n, i1 false) ret i16 %tmp1 } ; Generate a test and branch to handle zero inputs because bsr/bsf are very slow. define i32 @cttz_i32_zero_test(i32 %n) { ; X86-LABEL: cttz_i32_zero_test: ; X86: # %bb.0: ; X86-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-NEXT: testl %eax, %eax ; X86-NEXT: je .LBB14_1 ; X86-NEXT: # %bb.2: # %cond.false ; X86-NEXT: bsfl %eax, %eax ; X86-NEXT: retl ; X86-NEXT: .LBB14_1: ; X86-NEXT: movl $32, %eax ; X86-NEXT: retl ; ; X64-LABEL: cttz_i32_zero_test: ; X64: # %bb.0: ; X64-NEXT: testl %edi, %edi ; X64-NEXT: je .LBB14_1 ; X64-NEXT: # %bb.2: # %cond.false ; X64-NEXT: bsfl %edi, %eax ; X64-NEXT: retq ; X64-NEXT: .LBB14_1: ; X64-NEXT: movl $32, %eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: cttz_i32_zero_test: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: tzcntl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: cttz_i32_zero_test: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: tzcntl %edi, %eax ; X64-CLZ-NEXT: retq %tmp1 = call i32 @llvm.cttz.i32(i32 %n, i1 false) ret i32 %tmp1 } ; Generate a test and branch to handle zero inputs because bsr/bsf are very slow. define i64 @cttz_i64_zero_test(i64 %n) { ; X86-NOCMOV-LABEL: cttz_i64_zero_test: ; X86-NOCMOV: # %bb.0: ; X86-NOCMOV-NEXT: movl {{[0-9]+}}(%esp), %ecx ; X86-NOCMOV-NEXT: bsfl {{[0-9]+}}(%esp), %edx ; X86-NOCMOV-NEXT: movl $32, %eax ; X86-NOCMOV-NEXT: je .LBB15_2 ; X86-NOCMOV-NEXT: # %bb.1: ; X86-NOCMOV-NEXT: movl %edx, %eax ; X86-NOCMOV-NEXT: .LBB15_2: ; X86-NOCMOV-NEXT: testl %ecx, %ecx ; X86-NOCMOV-NEXT: jne .LBB15_3 ; X86-NOCMOV-NEXT: # %bb.4: ; X86-NOCMOV-NEXT: addl $32, %eax ; X86-NOCMOV-NEXT: xorl %edx, %edx ; X86-NOCMOV-NEXT: retl ; X86-NOCMOV-NEXT: .LBB15_3: ; X86-NOCMOV-NEXT: bsfl %ecx, %eax ; X86-NOCMOV-NEXT: xorl %edx, %edx ; X86-NOCMOV-NEXT: retl ; ; X86-CMOV-LABEL: cttz_i64_zero_test: ; X86-CMOV: # %bb.0: ; X86-CMOV-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-CMOV-NEXT: bsfl {{[0-9]+}}(%esp), %ecx ; X86-CMOV-NEXT: movl $32, %edx ; X86-CMOV-NEXT: cmovnel %ecx, %edx ; X86-CMOV-NEXT: addl $32, %edx ; X86-CMOV-NEXT: bsfl %eax, %eax ; X86-CMOV-NEXT: cmovel %edx, %eax ; X86-CMOV-NEXT: xorl %edx, %edx ; X86-CMOV-NEXT: retl ; ; X64-LABEL: cttz_i64_zero_test: ; X64: # %bb.0: ; X64-NEXT: testq %rdi, %rdi ; X64-NEXT: je .LBB15_1 ; X64-NEXT: # %bb.2: # %cond.false ; X64-NEXT: bsfq %rdi, %rax ; X64-NEXT: retq ; X64-NEXT: .LBB15_1: ; X64-NEXT: movl $64, %eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: cttz_i64_zero_test: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: testl %eax, %eax ; X86-CLZ-NEXT: jne .LBB15_1 ; X86-CLZ-NEXT: # %bb.2: ; X86-CLZ-NEXT: tzcntl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: addl $32, %eax ; X86-CLZ-NEXT: xorl %edx, %edx ; X86-CLZ-NEXT: retl ; X86-CLZ-NEXT: .LBB15_1: ; X86-CLZ-NEXT: tzcntl %eax, %eax ; X86-CLZ-NEXT: xorl %edx, %edx ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: cttz_i64_zero_test: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: tzcntq %rdi, %rax ; X64-CLZ-NEXT: retq %tmp1 = call i64 @llvm.cttz.i64(i64 %n, i1 false) ret i64 %tmp1 } ; Don't generate the cmovne when the source is known non-zero (and bsr would ; not set ZF). ; rdar://9490949 ; FIXME: The compare and branch are produced late in IR (by CodeGenPrepare), and ; codegen doesn't know how to delete the movl and je. define i32 @ctlz_i32_fold_cmov(i32 %n) { ; X86-LABEL: ctlz_i32_fold_cmov: ; X86: # %bb.0: ; X86-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-NEXT: orl $1, %eax ; X86-NEXT: je .LBB16_1 ; X86-NEXT: # %bb.2: # %cond.false ; X86-NEXT: bsrl %eax, %eax ; X86-NEXT: xorl $31, %eax ; X86-NEXT: retl ; X86-NEXT: .LBB16_1: ; X86-NEXT: movl $32, %eax ; X86-NEXT: retl ; ; X64-LABEL: ctlz_i32_fold_cmov: ; X64: # %bb.0: ; X64-NEXT: orl $1, %edi ; X64-NEXT: je .LBB16_1 ; X64-NEXT: # %bb.2: # %cond.false ; X64-NEXT: bsrl %edi, %eax ; X64-NEXT: xorl $31, %eax ; X64-NEXT: retq ; X64-NEXT: .LBB16_1: ; X64-NEXT: movl $32, %eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: ctlz_i32_fold_cmov: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: orl $1, %eax ; X86-CLZ-NEXT: lzcntl %eax, %eax ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: ctlz_i32_fold_cmov: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: orl $1, %edi ; X64-CLZ-NEXT: lzcntl %edi, %eax ; X64-CLZ-NEXT: retq %or = or i32 %n, 1 %tmp1 = call i32 @llvm.ctlz.i32(i32 %or, i1 false) ret i32 %tmp1 } ; Don't generate any xors when a 'ctlz' intrinsic is actually used to compute ; the most significant bit, which is what 'bsr' does natively. ; FIXME: We should probably select BSR instead of LZCNT in these circumstances. define i32 @ctlz_bsr(i32 %n) { ; X86-LABEL: ctlz_bsr: ; X86: # %bb.0: ; X86-NEXT: bsrl {{[0-9]+}}(%esp), %eax ; X86-NEXT: retl ; ; X64-LABEL: ctlz_bsr: ; X64: # %bb.0: ; X64-NEXT: bsrl %edi, %eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: ctlz_bsr: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: lzcntl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: xorl $31, %eax ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: ctlz_bsr: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: lzcntl %edi, %eax ; X64-CLZ-NEXT: xorl $31, %eax ; X64-CLZ-NEXT: retq %ctlz = call i32 @llvm.ctlz.i32(i32 %n, i1 true) %bsr = xor i32 %ctlz, 31 ret i32 %bsr } ; Generate a test and branch to handle zero inputs because bsr/bsf are very slow. ; FIXME: The compare and branch are produced late in IR (by CodeGenPrepare), and ; codegen doesn't know how to combine the $32 and $31 into $63. define i32 @ctlz_bsr_zero_test(i32 %n) { ; X86-LABEL: ctlz_bsr_zero_test: ; X86: # %bb.0: ; X86-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-NEXT: testl %eax, %eax ; X86-NEXT: je .LBB18_1 ; X86-NEXT: # %bb.2: # %cond.false ; X86-NEXT: bsrl %eax, %eax ; X86-NEXT: xorl $31, %eax ; X86-NEXT: xorl $31, %eax ; X86-NEXT: retl ; X86-NEXT: .LBB18_1: ; X86-NEXT: movl $32, %eax ; X86-NEXT: xorl $31, %eax ; X86-NEXT: retl ; ; X64-LABEL: ctlz_bsr_zero_test: ; X64: # %bb.0: ; X64-NEXT: testl %edi, %edi ; X64-NEXT: je .LBB18_1 ; X64-NEXT: # %bb.2: # %cond.false ; X64-NEXT: bsrl %edi, %eax ; X64-NEXT: xorl $31, %eax ; X64-NEXT: xorl $31, %eax ; X64-NEXT: retq ; X64-NEXT: .LBB18_1: ; X64-NEXT: movl $32, %eax ; X64-NEXT: xorl $31, %eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: ctlz_bsr_zero_test: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: lzcntl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: xorl $31, %eax ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: ctlz_bsr_zero_test: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: lzcntl %edi, %eax ; X64-CLZ-NEXT: xorl $31, %eax ; X64-CLZ-NEXT: retq %ctlz = call i32 @llvm.ctlz.i32(i32 %n, i1 false) %bsr = xor i32 %ctlz, 31 ret i32 %bsr } define i8 @cttz_i8_knownbits(i8 %x) { ; X86-LABEL: cttz_i8_knownbits: ; X86: # %bb.0: ; X86-NEXT: movb {{[0-9]+}}(%esp), %al ; X86-NEXT: orb $2, %al ; X86-NEXT: movzbl %al, %eax ; X86-NEXT: bsfl %eax, %eax ; X86-NEXT: # kill: def $al killed $al killed $eax ; X86-NEXT: retl ; ; X64-LABEL: cttz_i8_knownbits: ; X64: # %bb.0: ; X64-NEXT: orb $2, %dil ; X64-NEXT: movzbl %dil, %eax ; X64-NEXT: bsfl %eax, %eax ; X64-NEXT: # kill: def $al killed $al killed $eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: cttz_i8_knownbits: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: movb {{[0-9]+}}(%esp), %al ; X86-CLZ-NEXT: orb $2, %al ; X86-CLZ-NEXT: movzbl %al, %eax ; X86-CLZ-NEXT: tzcntl %eax, %eax ; X86-CLZ-NEXT: # kill: def $al killed $al killed $eax ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: cttz_i8_knownbits: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: orb $2, %dil ; X64-CLZ-NEXT: movzbl %dil, %eax ; X64-CLZ-NEXT: tzcntl %eax, %eax ; X64-CLZ-NEXT: # kill: def $al killed $al killed $eax ; X64-CLZ-NEXT: retq %x2 = or i8 %x, 2 %tmp = call i8 @llvm.cttz.i8(i8 %x2, i1 true ) %tmp2 = and i8 %tmp, 1 ret i8 %tmp2 } define i8 @ctlz_i8_knownbits(i8 %x) { ; X86-LABEL: ctlz_i8_knownbits: ; X86: # %bb.0: ; X86-NEXT: movb {{[0-9]+}}(%esp), %al ; X86-NEXT: orb $64, %al ; X86-NEXT: movzbl %al, %eax ; X86-NEXT: bsrl %eax, %eax ; X86-NEXT: xorl $7, %eax ; X86-NEXT: # kill: def $al killed $al killed $eax ; X86-NEXT: retl ; ; X64-LABEL: ctlz_i8_knownbits: ; X64: # %bb.0: ; X64-NEXT: orb $64, %dil ; X64-NEXT: movzbl %dil, %eax ; X64-NEXT: bsrl %eax, %eax ; X64-NEXT: xorl $7, %eax ; X64-NEXT: # kill: def $al killed $al killed $eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: ctlz_i8_knownbits: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: movb {{[0-9]+}}(%esp), %al ; X86-CLZ-NEXT: orb $64, %al ; X86-CLZ-NEXT: movzbl %al, %eax ; X86-CLZ-NEXT: lzcntl %eax, %eax ; X86-CLZ-NEXT: addl $-24, %eax ; X86-CLZ-NEXT: # kill: def $al killed $al killed $eax ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: ctlz_i8_knownbits: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: orb $64, %dil ; X64-CLZ-NEXT: movzbl %dil, %eax ; X64-CLZ-NEXT: lzcntl %eax, %eax ; X64-CLZ-NEXT: addl $-24, %eax ; X64-CLZ-NEXT: # kill: def $al killed $al killed $eax ; X64-CLZ-NEXT: retq %x2 = or i8 %x, 64 %tmp = call i8 @llvm.ctlz.i8(i8 %x2, i1 true ) %tmp2 = and i8 %tmp, 1 ret i8 %tmp2 } ; Make sure we can detect that the input is non-zero and avoid cmov after BSR ; This is relevant for 32-bit mode without lzcnt define i64 @ctlz_i64_zero_test_knownneverzero(i64 %n) { ; X86-NOCMOV-LABEL: ctlz_i64_zero_test_knownneverzero: ; X86-NOCMOV: # %bb.0: ; X86-NOCMOV-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-NOCMOV-NEXT: testl %eax, %eax ; X86-NOCMOV-NEXT: jne .LBB21_1 ; X86-NOCMOV-NEXT: # %bb.2: ; X86-NOCMOV-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-NOCMOV-NEXT: orl $1, %eax ; X86-NOCMOV-NEXT: bsrl %eax, %eax ; X86-NOCMOV-NEXT: xorl $31, %eax ; X86-NOCMOV-NEXT: orl $32, %eax ; X86-NOCMOV-NEXT: xorl %edx, %edx ; X86-NOCMOV-NEXT: retl ; X86-NOCMOV-NEXT: .LBB21_1: ; X86-NOCMOV-NEXT: bsrl %eax, %eax ; X86-NOCMOV-NEXT: xorl $31, %eax ; X86-NOCMOV-NEXT: xorl %edx, %edx ; X86-NOCMOV-NEXT: retl ; ; X86-CMOV-LABEL: ctlz_i64_zero_test_knownneverzero: ; X86-CMOV: # %bb.0: ; X86-CMOV-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-CMOV-NEXT: movl {{[0-9]+}}(%esp), %ecx ; X86-CMOV-NEXT: orl $1, %eax ; X86-CMOV-NEXT: bsrl %ecx, %edx ; X86-CMOV-NEXT: xorl $31, %edx ; X86-CMOV-NEXT: bsrl %eax, %eax ; X86-CMOV-NEXT: xorl $31, %eax ; X86-CMOV-NEXT: orl $32, %eax ; X86-CMOV-NEXT: testl %ecx, %ecx ; X86-CMOV-NEXT: cmovnel %edx, %eax ; X86-CMOV-NEXT: xorl %edx, %edx ; X86-CMOV-NEXT: retl ; ; X64-LABEL: ctlz_i64_zero_test_knownneverzero: ; X64: # %bb.0: ; X64-NEXT: orq $1, %rdi ; X64-NEXT: je .LBB21_1 ; X64-NEXT: # %bb.2: # %cond.false ; X64-NEXT: bsrq %rdi, %rax ; X64-NEXT: xorq $63, %rax ; X64-NEXT: retq ; X64-NEXT: .LBB21_1: ; X64-NEXT: movl $64, %eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: ctlz_i64_zero_test_knownneverzero: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: testl %eax, %eax ; X86-CLZ-NEXT: jne .LBB21_1 ; X86-CLZ-NEXT: # %bb.2: ; X86-CLZ-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: orl $1, %eax ; X86-CLZ-NEXT: lzcntl %eax, %eax ; X86-CLZ-NEXT: orl $32, %eax ; X86-CLZ-NEXT: xorl %edx, %edx ; X86-CLZ-NEXT: retl ; X86-CLZ-NEXT: .LBB21_1: ; X86-CLZ-NEXT: lzcntl %eax, %eax ; X86-CLZ-NEXT: xorl %edx, %edx ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: ctlz_i64_zero_test_knownneverzero: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: orq $1, %rdi ; X64-CLZ-NEXT: lzcntq %rdi, %rax ; X64-CLZ-NEXT: retq %o = or i64 %n, 1 %tmp1 = call i64 @llvm.ctlz.i64(i64 %o, i1 false) ret i64 %tmp1 } ; Make sure we can detect that the input is non-zero and avoid cmov after BSF ; This is relevant for 32-bit mode without tzcnt define i64 @cttz_i64_zero_test_knownneverzero(i64 %n) { ; X86-NOCMOV-LABEL: cttz_i64_zero_test_knownneverzero: ; X86-NOCMOV: # %bb.0: ; X86-NOCMOV-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-NOCMOV-NEXT: testl %eax, %eax ; X86-NOCMOV-NEXT: jne .LBB22_1 ; X86-NOCMOV-NEXT: # %bb.2: ; X86-NOCMOV-NEXT: movl $-2147483648, %eax # imm = 0x80000000 ; X86-NOCMOV-NEXT: orl {{[0-9]+}}(%esp), %eax ; X86-NOCMOV-NEXT: bsfl %eax, %eax ; X86-NOCMOV-NEXT: orl $32, %eax ; X86-NOCMOV-NEXT: xorl %edx, %edx ; X86-NOCMOV-NEXT: retl ; X86-NOCMOV-NEXT: .LBB22_1: ; X86-NOCMOV-NEXT: bsfl %eax, %eax ; X86-NOCMOV-NEXT: xorl %edx, %edx ; X86-NOCMOV-NEXT: retl ; ; X86-CMOV-LABEL: cttz_i64_zero_test_knownneverzero: ; X86-CMOV: # %bb.0: ; X86-CMOV-NEXT: movl {{[0-9]+}}(%esp), %ecx ; X86-CMOV-NEXT: movl $-2147483648, %eax # imm = 0x80000000 ; X86-CMOV-NEXT: orl {{[0-9]+}}(%esp), %eax ; X86-CMOV-NEXT: bsfl %ecx, %edx ; X86-CMOV-NEXT: bsfl %eax, %eax ; X86-CMOV-NEXT: orl $32, %eax ; X86-CMOV-NEXT: testl %ecx, %ecx ; X86-CMOV-NEXT: cmovnel %edx, %eax ; X86-CMOV-NEXT: xorl %edx, %edx ; X86-CMOV-NEXT: retl ; ; X64-LABEL: cttz_i64_zero_test_knownneverzero: ; X64: # %bb.0: ; X64-NEXT: movabsq $-9223372036854775808, %rax # imm = 0x8000000000000000 ; X64-NEXT: orq %rdi, %rax ; X64-NEXT: je .LBB22_1 ; X64-NEXT: # %bb.2: # %cond.false ; X64-NEXT: bsfq %rax, %rax ; X64-NEXT: retq ; X64-NEXT: .LBB22_1: ; X64-NEXT: movl $64, %eax ; X64-NEXT: retq ; ; X86-CLZ-LABEL: cttz_i64_zero_test_knownneverzero: ; X86-CLZ: # %bb.0: ; X86-CLZ-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: testl %eax, %eax ; X86-CLZ-NEXT: jne .LBB22_1 ; X86-CLZ-NEXT: # %bb.2: ; X86-CLZ-NEXT: movl $-2147483648, %eax # imm = 0x80000000 ; X86-CLZ-NEXT: orl {{[0-9]+}}(%esp), %eax ; X86-CLZ-NEXT: tzcntl %eax, %eax ; X86-CLZ-NEXT: orl $32, %eax ; X86-CLZ-NEXT: xorl %edx, %edx ; X86-CLZ-NEXT: retl ; X86-CLZ-NEXT: .LBB22_1: ; X86-CLZ-NEXT: tzcntl %eax, %eax ; X86-CLZ-NEXT: xorl %edx, %edx ; X86-CLZ-NEXT: retl ; ; X64-CLZ-LABEL: cttz_i64_zero_test_knownneverzero: ; X64-CLZ: # %bb.0: ; X64-CLZ-NEXT: movabsq $-9223372036854775808, %rax # imm = 0x8000000000000000 ; X64-CLZ-NEXT: orq %rdi, %rax ; X64-CLZ-NEXT: tzcntq %rax, %rax ; X64-CLZ-NEXT: retq %o = or i64 %n, -9223372036854775808 ; 0x8000000000000000 %tmp1 = call i64 @llvm.cttz.i64(i64 %o, i1 false) ret i64 %tmp1 }