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[/] [openrisc/] [trunk/] [or1ksim/] [testsuite/] [test-code-or1k/] [inst-set-test/] [is-sub-test.S] - Rev 733
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/* is-sub-test.S. l.sub instruction test of Or1ksim
*
* Copyright (C) 1999-2006 OpenCores
* Copyright (C) 2010 Embecosm Limited
*
* Contributors various OpenCores participants
* Contributor Jeremy Bennett <jeremy.bennett@embecosm.com>
*
* This file is part of OpenRISC 1000 Architectural Simulator.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 3 of the License, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along
* with this program. If not, see <http: www.gnu.org/licenses/>.
*/
/* ----------------------------------------------------------------------------
* Coding conventions are described in inst-set-test.S
* ------------------------------------------------------------------------- */
/* ----------------------------------------------------------------------------
* Test coverage
*
* The l.sub instruction should set the carry and overflow flags.
*
* Problems in this area were reported in Bugs 1782, 1783 and 1784. Having
* fixed the problem, this is (in good software engineering style), a
* regression test to go with the fix.
*
* This is not a comprehensive test of any instruction (yet).
*
* Of course what is really needed is a comprehensive instruction test...
* ------------------------------------------------------------------------- */
#include "inst-set-test.h"
/* ----------------------------------------------------------------------------
* A macro to carry out a test of subtraction in registers
*
*
* Arguments
* set_flags: Flags to set in the SR
* clr_flags: Flags to clear in the SR
* op1: First operand value
* op2: Second operand value
* res: Expected result
* cy: Expected carry flag
* ov: Expected overflow flag
* ------------------------------------------------------------------------- */
#define TEST_SUB(set_flags, clr_flags, op1, op2, res, cy, ov) \
l.mfspr r3,r0,SPR_SR ;\
LOAD_CONST (r2, set_flags) /* Set flags */ ;\
l.or r3,r3,r2 ;\
LOAD_CONST (r2, ~clr_flags) /* Clear flags */ ;\
l.and r3,r3,r2 ;\
l.mtspr r0,r3,SPR_SR ;\
;\
LOAD_CONST (r5,op1) /* Load numbers to subtract */ ;\
LOAD_CONST (r6,op2) ;\
l.mtspr r0,r0,SPR_EPCR_BASE /* Clear record */ ;\
50: l.sub r4,r5,r6 ;\
l.mfspr r2,r0,SPR_SR /* So we can examine flags */ ;\
l.mfspr r5,r0,SPR_EPCR_BASE /* What triggered exception */ ;\
PUSH (r5) /* Save EPCR for later */ ;\
PUSH (r2) ;\
PUSH (r4) /* Save result for later */ ;\
;\
PUTS (" 0x") ;\
PUTH (op1) ;\
PUTS (" - 0x") ;\
PUTH (op2) ;\
PUTS (" = 0x") ;\
PUTH (res) ;\
PUTS (": ") ;\
POP (r4) ;\
CHECK_RES1 (r4, res) ;\
;\
POP(r2) /* Retrieve SR */ ;\
PUSH(r2) ;\
LOAD_CONST (r4, SPR_SR_CY) /* The carry bit */ ;\
l.and r2,r2,r4 ;\
l.sfeq r2,r4 ;\
CHECK_FLAG ("- carry flag set: ", cy) ;\
;\
POP(r2) /* Retrieve SR */ ;\
LOAD_CONST (r4, SPR_SR_OV) /* The overflow bit */ ;\
l.and r2,r2,r4 ;\
l.sfeq r2,r4 ;\
CHECK_FLAG ("- overflow flag set: ", ov) ;\
;\
POP (r2) /* Retrieve EPCR */ ;\
LOAD_CONST (r4, 50b) /* The opcode of interest */ ;\
l.and r2,r2,r4 ;\
l.sfeq r2,r4 ;\
l.bnf 53f ;\
;\
PUTS (" - exception triggered: TRUE\n") ;\
l.j 54f ;\
l.nop ;\
;\
53: PUTS (" - exception triggered: FALSE\n") ;\
54:
/* ----------------------------------------------------------------------------
* Start of code
* ------------------------------------------------------------------------- */
.section .text
.global _start
_start:
l.mfspr r3,r0,SPR_SR
LOAD_CONST (r2, ~SPR_SR_OVE) /* Clear OVE */
l.and r3,r3,r2
l.mtspr r0,r3,SPR_SR
LOAD_STR (r3, " ** OVE flag cleared **\n")
l.jal _puts
l.nop
/* ----------------------------------------------------------------------------
* Test of subtract signed, l.sub
* ------------------------------------------------------------------------- */
_sub:
LOAD_STR (r3, "l.sub\n")
l.jal _puts
l.nop
/* Subtract two small positive numbers. Sets the carry, but never the
overflow if the result is negative. */
TEST_SUB (0, SPR_SR_CY | SPR_SR_OV,
0x00000003, 0x00000002, 0x00000001,
FALSE, FALSE)
TEST_SUB (0, SPR_SR_CY | SPR_SR_OV,
0x00000001, 0x00000002, 0xffffffff,
TRUE, FALSE)
/* Check carry in is ignored. */
TEST_SUB (SPR_SR_CY, SPR_SR_OV,
0x00000003, 0x00000002, 0x00000001,
FALSE, FALSE)
/* Subtract two small negative numbers. Sets the carry flag if the
result is negative, but never the overflow flag. */
TEST_SUB (0, SPR_SR_CY | SPR_SR_OV,
0xfffffffd, 0xfffffffe, 0xffffffff,
TRUE, FALSE)
TEST_SUB (0, SPR_SR_CY | SPR_SR_OV,
0xffffffff, 0xfffffffe, 0x00000001,
FALSE, FALSE)
/* Subtract two quite large positive numbers. Should set neither the
overflow nor the carry flag. */
TEST_SUB (0, SPR_SR_CY | SPR_SR_OV,
0x7fffffff, 0x3fffffff, 0x40000000,
FALSE, FALSE)
/* Subtract two quite large negative numbers. Should set neither the
overflow nor the carry flag. */
TEST_SUB (0, SPR_SR_CY | SPR_SR_OV,
0x40000000, 0x40000000, 0x00000000,
FALSE, FALSE)
/* Subtract two large positive numbers with a negative result. Should
set the carry, but not the overflow flag. */
TEST_SUB (0, SPR_SR_CY | SPR_SR_OV,
0x3fffffff, 0x40000000, 0xffffffff,
TRUE, FALSE)
/* Subtract two large negative numbers with a positive result. Should
set niether the carry nor the overflow flag. */
TEST_SUB (0, SPR_SR_CY | SPR_SR_OV,
0x40000000, 0x3fffffff, 0x00000001,
FALSE, FALSE)
/* Subtract a large positive from a large negative number. Should set
overflow but not the carry flag. */
TEST_SUB (0, SPR_SR_CY | SPR_SR_OV,
0x80000000, 0x7fffffff, 0x00000001,
FALSE, TRUE)
/* Subtract a large negative from a large positive number. Should set
both the overflow and carry flags. */
TEST_SUB (0, SPR_SR_CY | SPR_SR_OV,
0x7fffffff, 0x80000000, 0xffffffff,
TRUE, TRUE)
/* Check that range exceptions are triggered */
l.mfspr r3,r0,SPR_SR
LOAD_CONST (r2, SPR_SR_OVE) /* Set OVE */
l.or r3,r3,r2
l.mtspr r0,r3,SPR_SR
LOAD_STR (r3, " ** OVE flag set **\n")
l.jal _puts
l.nop
/* Check that an overflow alone causes a RANGE Exception. */
TEST_SUB (0, SPR_SR_CY | SPR_SR_OV,
0x80000000, 0x7fffffff, 0x00000001,
FALSE, TRUE)
/* Check that a carry alone does not cause a RANGE Exception. */
TEST_SUB (0, SPR_SR_CY | SPR_SR_OV,
0x3fffffff, 0x40000000, 0xffffffff,
TRUE, FALSE)
/* Check that carry and overflow together cause an exception. */
TEST_SUB (0, SPR_SR_CY | SPR_SR_OV,
0x7fffffff, 0x80000000, 0xffffffff,
TRUE, TRUE)
/* Finished checking range exceptions */
l.mfspr r3,r0,SPR_SR
LOAD_CONST (r2, ~SPR_SR_OVE) /* Clear OVE */
l.and r3,r3,r2
l.mtspr r0,r3,SPR_SR
LOAD_STR (r3, " ** OVE flag cleared **\n")
l.jal _puts
l.nop
/* ----------------------------------------------------------------------------
* All done
* ------------------------------------------------------------------------- */
_exit:
LOAD_STR (r3, "Test completed\n")
l.jal _puts
l.nop
TEST_EXIT
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