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[/] [openrisc/] [trunk/] [or1ksim/] [testsuite/] [test-code-or1k/] [inst-set-test/] [is-add-test.S] - Rev 867

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/* is-add-test.S. l.add, l.addc, l.addi and l.addic 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.add, l.addc, l.addi and l.addic instructions should set the carry and
 * overflow flags.
 *
 * In addition the l.addc and l.addic instructions should add in the carry
 * bit.
 *
 * Problems in this area were reported in Bugs 1771 and 1776. 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 addition in registers
 *
 *
 * Arguments
 *   set_flags: Flags to set in the SR
 *   clr_flags: Flags to clear in the SR
 *   opc:       The opcode
 *   op1:       First operand value
 *   op2:       Second operand value
 *   res:       Expected result
 *   cy:        Expected carry flag
 *   ov:        Expected overflow flag
 * ------------------------------------------------------------------------- */
#define TEST_ADD(set_flags, clr_flags, opc, 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 add */       ;\
        LOAD_CONST (r6,op2)                                             ;\
        l.mtspr r0,r0,SPR_EPCR_BASE     /* Clear record */              ;\
50:     opc     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)                                                      ;\
                                                                        ;\
        LOAD_CONST (r2, set_flags)      /* Are we adding in carry */    ;\
        LOAD_CONST (r4, SPR_SR_CY)                                      ;\
        l.and   r2,r2,r4                                                ;\
        l.sfeq  r2,r4                                                   ;\
        l.bnf   51f                                                     ;\
        l.nop                                                           ;\
                                                                        ;\
        PUTS (" + c")                   /* CY set to add in? */         ;\
        l.j     52f                                                     ;\
        l.nop                                                           ;\
                                                                        ;\
51:     PUTS ("    ")                   /* CY clear to add in? */       ;\
                                                                        ;\
52:     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:     

/* ----------------------------------------------------------------------------
 * A macro to carry out a test of addition with an immediate value
 *
 *
 * Arguments
 *   set_flags: Flags to set in the SR
 *   clr_flags: Flags to clear in the SR
 *   opc:       The opcode
 *   op1:       First operand value
 *   op2:       Second operand value (immediate)
 *   res:       Expected result
 *   cy:        Expected carry flag
 *   ov:        Expected overflow flag
 * ------------------------------------------------------------------------- */
#define TEST_ADDI(set_flags, clr_flags, opc, 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 add */       ;\
        l.mtspr r0,r0,SPR_EPCR_BASE     /* Clear record */              ;\
55:     opc     r4,r5,op2                                               ;\
        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)                                                      ;\
                                                                        ;\
        LOAD_CONST (r2, set_flags)      /* Are we adding in carry */    ;\
        LOAD_CONST (r4, SPR_SR_CY)                                      ;\
        l.and   r2,r2,r4                                                ;\
        l.sfeq  r2,r4                                                   ;\
        l.bnf   56f                                                     ;\
        l.nop                                                           ;\
                                                                        ;\
        PUTS (" + c")                   /* CY set to add in? */         ;\
        l.j     57f                                                     ;\
        l.nop                                                           ;\
                                                                        ;\
56:     PUTS ("    ")                   /* CY clear to add in? */       ;\
                                                                        ;\
57:     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, 55b)            /* The opcode of interest */    ;\
        l.and   r2,r2,r4                                                ;\
        l.sfeq  r2,r4                                                   ;\
        l.bnf   58f                                                     ;\
                                                                        ;\
        PUTS ("  - exception triggered: TRUE\n")                        ;\
        l.j     59f                                                     ;\
        l.nop                                                           ;\
                                                                        ;\
58:     PUTS ("  - exception triggered: FALSE\n")                       ;\
59:     

        
/* ----------------------------------------------------------------------------
 * 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 add signed, l.add
 * ------------------------------------------------------------------------- */
_add:
        LOAD_STR (r3, "l.add\n")
        l.jal   _puts
        l.nop

        /* Add two small positive numbers */
        TEST_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.add, 1, 2, 3,
                  FALSE, FALSE)

        /* Check carry in is ignored. */
        TEST_ADD (SPR_SR_CY, SPR_SR_OV,
                  l.add, 1, 2, 3,
                  FALSE, FALSE)

        /* Add two small negative numbers. Sets the carry flag but not the
           overflow flag. */
        TEST_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.add, 0xffffffff, 0xfffffffe, 0xfffffffd,
                  TRUE, FALSE)

        /* Add two quite large positive numbers. Should set neither the
           overflow nor the carry flag. */
        TEST_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.add, 0x40000000, 0x3fffffff, 0x7fffffff,
                  FALSE, FALSE)

        /* Add two large positive numbers. Should set the overflow, but not
           the carry flag. */
        TEST_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.add, 0x40000000, 0x40000000, 0x80000000,
                  FALSE, TRUE)

        /* Add two quite large negative numbers. Should set the carry, but not
           the overflow flag. */
        TEST_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.add, 0xc0000000, 0xc0000000, 0x80000000,
                  TRUE, FALSE)

        /* Add two large negative numbers. Should set both the overflow and
           carry flags. */
        TEST_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.add, 0xbfffffff, 0xbfffffff, 0x7ffffffe,
                  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_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.add, 0x40000000, 0x40000000, 0x80000000,
                  FALSE, TRUE)

        /* Check that a carry alone does not cause a RANGE Exception. */
        TEST_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.add, 0xffffffff, 0xfffffffe, 0xfffffffd,
                  TRUE, FALSE)

        /* Check that carry and overflow together cause an exception. */
        TEST_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.add, 0xbfffffff, 0xbfffffff, 0x7ffffffe,
                  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

/* ----------------------------------------------------------------------------
 * Test of add signed and carry, l.addc
 * ------------------------------------------------------------------------- */
_addc:
        LOAD_STR (r3, "l.addc\n")
        l.jal   _puts
        l.nop

        /* Add two small positive numbers */
        TEST_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.addc, 1, 2, 3,
                  FALSE, FALSE)

        /* Add two small negative numbers. Sets the carry flag but not the
           overflow flag. */
        TEST_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.addc, 0xffffffff, 0xfffffffe, 0xfffffffd,
                  TRUE, FALSE)

        /* Add two quite large positive numbers. Should set neither the
           overflow nor the carry flag. */
        TEST_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.addc, 0x40000000, 0x3fffffff, 0x7fffffff,
                  FALSE, FALSE)

        /* Add two quite large positive numbers with a carry in. Should set
           the overflow but not the carry flag. */
        TEST_ADD (SPR_SR_CY, SPR_SR_OV,
                  l.addc, 0x40000000, 0x3fffffff, 0x80000000,
                  FALSE, TRUE)

        /* Add two large positive numbers. Should set the overflow, but not
           the carry flag. */
        TEST_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.addc, 0x40000000, 0x40000000, 0x80000000,
                  FALSE, TRUE)

        /* Add the largest unsigned value to zero with a carry. This
           potentially can break a simplistic test for carry that does not
           consider the carry flag properly. Do it both ways around. */
        TEST_ADD (SPR_SR_CY, SPR_SR_OV,
                  l.addc, 0xffffffff, 0x00000000, 0x00000000,
                  TRUE, FALSE)

        TEST_ADD (SPR_SR_CY, SPR_SR_OV,
                  l.addc, 0x00000000, 0xffffffff, 0x00000000,
                  TRUE, FALSE)

        /* Add two quite large negative numbers. Should set the carry, but not
           the overflow flag. flag. */
        TEST_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.addc, 0xc0000000, 0xc0000000, 0x80000000,
                  TRUE, FALSE)

        /* Add two quite large negative numbers that would overflow, with a
           carry that just avoids the overflow. Should set the carry, but not
           the overflow flag. flag. */
        TEST_ADD (SPR_SR_CY, SPR_SR_OV,
                  l.addc, 0xc0000000, 0xbfffffff, 0x80000000,
                  TRUE, FALSE)

        /* Add two large negative numbers. Should set both the overflow and
           carry flags. */
        TEST_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.addc, 0xbfffffff, 0xbfffffff, 0x7ffffffe,
                  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, even when it
           is the carry that causes the overflow. */
        TEST_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.addc, 0x40000000, 0x40000000, 0x80000000,
                  FALSE, TRUE)

        TEST_ADD (SPR_SR_CY, SPR_SR_OV,
                  l.addc, 0x40000000, 0x3fffffff, 0x80000000,
                  FALSE, TRUE)

        /* Check that a carry alone does not cause a RANGE Exception, even
           when it is the carry that causes the overflow. */
        TEST_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.addc, 0xffffffff, 0xfffffffe, 0xfffffffd,
                  TRUE, FALSE)

        TEST_ADD (SPR_SR_CY, SPR_SR_OV,
                  l.addc, 0x00000000, 0xffffffff, 0x00000000,
                  TRUE, FALSE)

        /* Check that carry and overflow together cause an exception. */
        TEST_ADD (0, SPR_SR_CY | SPR_SR_OV,
                  l.addc, 0xbfffffff, 0xbfffffff, 0x7ffffffe,
                  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

/* ----------------------------------------------------------------------------
 * Test of add signed immediate, l.addi
 * ------------------------------------------------------------------------- */
_addi:
        LOAD_STR (r3, "l.addi\n")
        l.jal   _puts
        l.nop

        /* Add two small positive numbers */
        TEST_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addi, 1, 2, 3,
                   FALSE, FALSE)

        /* Check carry in is ignored. */
        TEST_ADDI (SPR_SR_CY, SPR_SR_OV,
                   l.addi, 1, 2, 3,
                   FALSE, FALSE)

        /* Add two small negative numbers. Sets the carry flag but not the
           overflow flag. */
        TEST_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addi, 0xffffffff, 0xfffe, 0xfffffffd,
                   TRUE, FALSE)

        /* Add two quite large positive numbers. Should set neither the
           overflow nor the carry flag. */
        TEST_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addi, 0x7fff8000, 0x7fff, 0x7fffffff,
                   FALSE, FALSE)

        /* Add two large positive numbers. Should set the overflow, but not
           the carry flag. */
        TEST_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addi, 0x7fffc000, 0x4000, 0x80000000,
                   FALSE, TRUE)

        /* Add two quite large negative numbers. Should set the carry, but not
           the overflow flag. */
        TEST_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addi, 0x80008000, 0x8000, 0x80000000,
                   TRUE, FALSE)

        /* Add two large negative numbers. Should set both the overflow and
           carry flags. */
        TEST_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addi, 0x80007fff, 0x8000, 0x7fffffff,
                   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_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addi, 0x7fffc000, 0x4000, 0x80000000,
                   FALSE, TRUE)

        /* Check that a carry alone does not cause a RANGE Exception. */
        TEST_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addi, 0xffffffff, 0xfffe, 0xfffffffd,
                   TRUE, FALSE)

        /* Check that carry and overflow together cause an exception. */
        TEST_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addi, 0x80007fff, 0x8000, 0x7fffffff,
                   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

/* ----------------------------------------------------------------------------
 * Test of add signed and carry, l.addic
 * ------------------------------------------------------------------------- */
_addic:
        LOAD_STR (r3, "l.addic\n")
        l.jal   _puts
        l.nop

        /* Add two small positive numbers */
        TEST_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addic, 1, 2, 3,
                   FALSE, FALSE)

        /* Add two small negative numbers. Sets the carry flag but not the
           overflow flag. */
        TEST_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addic, 0xffffffff, 0xfffe, 0xfffffffd,
                   TRUE, FALSE)

        /* Add two quite large positive numbers. Should set neither the
           overflow nor the carry flag. */
        TEST_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addic, 0x7fff8000, 0x7fff, 0x7fffffff,
                   FALSE, FALSE)

        /* Add two quite large positive numbers with a carry in. Should set
           the overflow but not the carry flag. */
        TEST_ADDI (SPR_SR_CY, SPR_SR_OV,
                   l.addic, 0x7fff8000, 0x7fff, 0x80000000,
                   FALSE, TRUE)

        /* Add two large positive numbers. Should set the overflow, but not
           the carry flag. */
        TEST_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addic, 0x7fffc000, 0x4000, 0x80000000,
                   FALSE, TRUE)

        /* Add the largest unsigned value to zero with a carry. This
           potentially can break a simplistic test for carry that does not
           consider the carry flag properly. Do it both ways around. */
        TEST_ADDI (SPR_SR_CY, SPR_SR_OV,
                   l.addic, 0xffffffff, 0x0000, 0x00000000,
                   TRUE, FALSE)

        TEST_ADDI (SPR_SR_CY, SPR_SR_OV,
                   l.addic, 0x00000000, 0xffff, 0x00000000,
                   TRUE, FALSE)

        /* Add two quite large negative numbers. Should set the carry, but not
           the overflow flag. flag. */
        TEST_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addic, 0x80008000, 0x8000, 0x80000000,
                   TRUE, FALSE)

        /* Add two quite large negative numbers that would overflow, with a
           carry that just avoids the overflow. Should set the carry, but not
           the overflow flag. flag. */
        TEST_ADDI (SPR_SR_CY, SPR_SR_OV,
                   l.addic, 0x80007fff, 0x8000, 0x80000000,
                   TRUE, FALSE)

        /* Add two large negative numbers. Should set both the overflow and
           carry flags. */
        TEST_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addic, 0x80007fff, 0x8000, 0x7fffffff,
                   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, even when it
           is the carry that causes the overflow. */
        TEST_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addic, 0x7fffc000, 0x4000, 0x80000000,
                   FALSE, TRUE)

        TEST_ADDI (SPR_SR_CY, SPR_SR_OV,
                   l.addic, 0x7fffc000, 0x3fff, 0x80000000,
                   FALSE, TRUE)

        /* Check that a carry alone does not cause a RANGE Exception, even
           when it is the carry that causes the overflow. */
        TEST_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addic, 0xffffffff, 0xfffe, 0xfffffffd,
                   TRUE, FALSE)

        TEST_ADDI (SPR_SR_CY, SPR_SR_OV,
                   l.addic, 0x00000000, 0xffff, 0x00000000,
                   TRUE, FALSE)

        /* Check that carry and overflow together cause an exception. */
        TEST_ADDI (0, SPR_SR_CY | SPR_SR_OV,
                   l.addic, 0x80007fff, 0x8000, 0x7fffffff,
                   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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