diff options
Diffstat (limited to 'lib/builtins/arm/umodsi3.S')
| -rw-r--r-- | lib/builtins/arm/umodsi3.S | 60 |
1 files changed, 29 insertions, 31 deletions
diff --git a/lib/builtins/arm/umodsi3.S b/lib/builtins/arm/umodsi3.S index 069fad34cb9c..5ab78de17853 100644 --- a/lib/builtins/arm/umodsi3.S +++ b/lib/builtins/arm/umodsi3.S @@ -1,16 +1,15 @@ -/*===-- umodsi3.S - 32-bit unsigned integer modulus -----------------------===// - * - * The LLVM Compiler Infrastructure - * - * This file is dual licensed under the MIT and the University of Illinois Open - * Source Licenses. See LICENSE.TXT for details. - * - *===----------------------------------------------------------------------===// - * - * This file implements the __umodsi3 (32-bit unsigned integer modulus) - * function for the ARM 32-bit architecture. - * - *===----------------------------------------------------------------------===*/ +//===-- umodsi3.S - 32-bit unsigned integer modulus -----------------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +// +// This file implements the __umodsi3 (32-bit unsigned integer modulus) +// function for the ARM 32-bit architecture. +// +//===----------------------------------------------------------------------===// #include "../assembly.h" @@ -38,26 +37,25 @@ DEFINE_COMPILERRT_FUNCTION(__umodsi3) cmp r0, r1 IT(cc) JMPc(lr, cc) - /* - * Implement division using binary long division algorithm. - * - * r0 is the numerator, r1 the denominator. - * - * The code before JMP computes the correct shift I, so that - * r0 and (r1 << I) have the highest bit set in the same position. - * At the time of JMP, ip := .Ldiv0block - 8 * I. - * This depends on the fixed instruction size of block. - * For ARM mode, this is 8 Bytes, for THUMB mode 10 Bytes. - * - * block(shift) implements the test-and-update-quotient core. - * It assumes (r0 << shift) can be computed without overflow and - * that (r0 << shift) < 2 * r1. The quotient is stored in r3. - */ + + // Implement division using binary long division algorithm. + // + // r0 is the numerator, r1 the denominator. + // + // The code before JMP computes the correct shift I, so that + // r0 and (r1 << I) have the highest bit set in the same position. + // At the time of JMP, ip := .Ldiv0block - 8 * I. + // This depends on the fixed instruction size of block. + // For ARM mode, this is 8 Bytes, for THUMB mode 10 Bytes. + // + // block(shift) implements the test-and-update-quotient core. + // It assumes (r0 << shift) can be computed without overflow and + // that (r0 << shift) < 2 * r1. The quotient is stored in r3. # ifdef __ARM_FEATURE_CLZ clz ip, r0 clz r3, r1 - /* r0 >= r1 implies clz(r0) <= clz(r1), so ip <= r3. */ + // r0 >= r1 implies clz(r0) <= clz(r1), so ip <= r3. sub r3, r3, ip # if defined(USE_THUMB_2) adr ip, LOCAL_LABEL(div0block) + 1 @@ -94,7 +92,7 @@ DEFINE_COMPILERRT_FUNCTION(__umodsi3) movhs r2, r3 subhs ip, ip, #(2 * 8) - /* Last block, no need to update r2 or r3. */ + // Last block, no need to update r2 or r3. cmp r1, r2, lsr #1 subls ip, ip, #(1 * 8) @@ -142,7 +140,7 @@ DEFINE_COMPILERRT_FUNCTION(__umodsi3) LOCAL_LABEL(div0block): block(0) JMP(lr) -#endif /* __ARM_ARCH_EXT_IDIV__ */ +#endif // __ARM_ARCH_EXT_IDIV__ LOCAL_LABEL(divby0): mov r0, #0 |