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| author | Jozef Lawrynowicz <jozef.l@mittosystems.com> | 2020-07-28 10:36:10 +0100 |
|---|---|---|
| committer | Jozef Lawrynowicz <jozef.l@mittosystems.com> | 2020-08-05 15:02:30 +0100 |
| commit | e8a387fb5f91cdb9674f19703c0e7bfbaf895a84 (patch) | |
| tree | 162d6decb4ea00d04438bf2e2ce3620cd8b1b9da /sim/testsuite | |
| parent | 5555c86d3e85e85d76555acdb955aba062beb02f (diff) | |
| download | gdb-e8a387fb5f91cdb9674f19703c0e7bfbaf895a84.zip gdb-e8a387fb5f91cdb9674f19703c0e7bfbaf895a84.tar.gz gdb-e8a387fb5f91cdb9674f19703c0e7bfbaf895a84.tar.bz2 | |
MSP430: sim: Fix incorrect simulation of unsigned widening multiply
Operand sizes used for simulation of MSP430 hardware multiply
operations are not aligned with the sizes used on the target, resulting
in the simulator storing signed operands with too much precision.
Additionally, simulation of unsigned multiplication is missing explicit
casts to prevent any implicit sign extension.
gcc.c-torture/execute/pr91450-1.c uses unsigned widening multiplication
of 32-bit operands -4 and 2, to produce a 64-bit result:
0xffff fffc * 0x2 = 0x1 ffff fff8
If -4 is stored in 64-bit precision, then the multiplication is
essentially signed and the result is -8 in 64-bit precision
(0xffff ffff ffff fffc), which is not correct.
sim/msp430/ChangeLog:
* msp430-sim.c (put_op): For unsigned multiplication, explicitly cast
operands to the unsigned type before multiplying.
* msp430-sim.h (struct msp430_cpu_state): Fix types used to store hwmult
operands.
sim/testsuite/sim/msp430/ChangeLog:
* mpyull_hwmult.s: New test.
Diffstat (limited to 'sim/testsuite')
| -rw-r--r-- | sim/testsuite/sim/msp430/ChangeLog | 4 | ||||
| -rw-r--r-- | sim/testsuite/sim/msp430/mpyull_hwmult.s | 55 |
2 files changed, 59 insertions, 0 deletions
diff --git a/sim/testsuite/sim/msp430/ChangeLog b/sim/testsuite/sim/msp430/ChangeLog index 7dc370f..cd6b195 100644 --- a/sim/testsuite/sim/msp430/ChangeLog +++ b/sim/testsuite/sim/msp430/ChangeLog @@ -1,3 +1,7 @@ +2020-08-05 Jozef Lawrynowicz <jozef.l@mittosystems.com> + + * mpyull_hwmult.s: New test. + 2020-01-22 Jozef Lawrynowicz <jozef.l@mittosystems.com> * rrux.s: New test. diff --git a/sim/testsuite/sim/msp430/mpyull_hwmult.s b/sim/testsuite/sim/msp430/mpyull_hwmult.s new file mode 100644 index 0000000..911fa11 --- /dev/null +++ b/sim/testsuite/sim/msp430/mpyull_hwmult.s @@ -0,0 +1,55 @@ +# Test that unsigned widening multiplication of 32-bit operands to produce a +# 64-bit result is simulated correctly, when using 32-bit or F5series hardware +# multiply functionality. +# 0xffff fffc * 0x2 = 0x1 ffff fff8 +# mach: msp430 + +# 32-bit hwmult register addresses +.set MPY32L, 0x0140 +.set MPY32H, 0x0142 +.set OP2L, 0x0150 +.set OP2H, 0x0152 +.set RES0, 0x0154 +.set RES1, 0x0156 +.set RES2, 0x0158 +.set RES3, 0x015A + +# F5series hwmult register addresses +.set MPY32L_F5, 0x04D0 +.set MPY32H_F5, 0x04D2 +.set OP2L_F5, 0x04E0 +.set OP2H_F5, 0x04E2 +.set RES0_F5, 0x04E4 +.set RES1_F5, 0x04E6 +.set RES2_F5, 0x04E8 +.set RES3_F5, 0x04EA + +.include "testutils.inc" + + start + + ; Test 32bit hwmult + MOV.W #2, &MPY32L ; Load operand 1 Low into multiplier + MOV.W #0, &MPY32H ; Load operand 1 High into multiplier + MOV.W #-4, &OP2L ; Load operand 2 Low into multiplier + MOV.W #-1, &OP2H ; Load operand 2 High, trigger MPY + + CMP.W #-8, &RES0 { JNE .L5 + CMP.W #-1, &RES1 { JNE .L5 + CMP.W #1, &RES2 { JNE .L5 + CMP.W #0, &RES3 { JNE .L5 + + ; Test f5series hwmult + MOV.W #2, &MPY32L_F5 + MOV.W #0, &MPY32H_F5 + MOV.W #-4, &OP2L_F5 + MOV.W #-1, &OP2H_F5 + + CMP.W #-8, &RES0_F5 { JNE .L5 + CMP.W #-1, &RES1_F5 { JNE .L5 + CMP.W #1, &RES2_F5 { JNE .L5 + CMP.W #0, &RES3_F5 { JEQ .L6 +.L5: + fail +.L6: + pass |