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Diffstat (limited to 'runtime/arm/i64_shl.s')
| -rw-r--r-- | runtime/arm/i64_shl.s | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/runtime/arm/i64_shl.s b/runtime/arm/i64_shl.s new file mode 100644 index 0000000..8014f88 --- /dev/null +++ b/runtime/arm/i64_shl.s @@ -0,0 +1,60 @@ +@ ***************************************************************** +@ +@ The Compcert verified compiler +@ +@ Xavier Leroy, INRIA Paris-Rocquencourt +@ +@ Copyright (c) 2013 Institut National de Recherche en Informatique et +@ en Automatique. +@ +@ Redistribution and use in source and binary forms, with or without +@ modification, are permitted provided that the following conditions are met: +@ * Redistributions of source code must retain the above copyright +@ notice, this list of conditions and the following disclaimer. +@ * Redistributions in binary form must reproduce the above copyright +@ notice, this list of conditions and the following disclaimer in the +@ documentation and/or other materials provided with the distribution. +@ * Neither the name of the <organization> nor the +@ names of its contributors may be used to endorse or promote products +@ derived from this software without specific prior written permission. +@ +@ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +@ "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +@ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +@ A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT +@ HOLDER> BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, +@ EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, +@ PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR +@ PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF +@ LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING +@ NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS +@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +@ +@ ********************************************************************* + +@ Helper functions for 64-bit integer arithmetic. ARM version. + + .text + +@@@ Shift left + +@ Note on ARM shifts: the shift amount is taken modulo 256. +@ Therefore, unsigned shifts by 32 bits or more produce 0. + + .global __i64_shl +__i64_shl: + and r2, r2, #63 @ normalize amount to 0...63 + rsbs r3, r2, #32 @ r3 = 32 - amount + ble 1f @ branch if <= 0, namely if amount >= 32 + mov r1, r1, lsl r2 + orr r1, r0, lsr r3 + mov r0, r0, lsl r2 + bx lr +1: + sub r2, r2, #32 + mov r1, r0, lsl r2 + mov r0, #0 + bx lr + .type __i64_shl, %function + .size __i64_shl, . - __i64_shl + |