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authorChris Demetriou <cgd@google.com>2002-05-01 17:26:14 +0000
committerChris Demetriou <cgd@google.com>2002-05-01 17:26:14 +0000
commit402586aa260ba9b74e3a2382276cf31a7abc2b6b (patch)
tree9d41b87e0d4643c93052427e8966e01a70c9c35a /sim/mips/mips.igen
parenta6befae84def7b445a76e360deba6dde20e03052 (diff)
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2002-05-01 Chris Demetriou <cgd@broadcom.com>
* cp1.c (store_fpr): Remove #ifdef'd out call to UndefinedResult which wouldn't compile anyway. * sim-main.h (unpredictable_action): New function prototype. (Unpredictable): Define to call igen function unpredictable(). (NotWordValue): New macro to call igen function not_word_value(). (UndefinedResult): Remove. * interp.c (undefined_result): Remove. (unpredictable_action): New function. * mips.igen (not_word_value, unpredictable): New functions. (ADD, ADDI, do_addiu, do_addu, BGEZAL, BGEZALL, BLTZAL, BLTZALL) (CLO, CLZ, MADD, MADDU, MSUB, MSUBU, MUL, do_mult, do_multu) (do_sra, do_srav, do_srl, do_srlv, SUB, do_subu): Invoke NotWordValue() to check for unpredictable inputs, then Unpredictable() to handle them.
Diffstat (limited to 'sim/mips/mips.igen')
-rw-r--r--sim/mips/mips.igen110
1 files changed, 110 insertions, 0 deletions
diff --git a/sim/mips/mips.igen b/sim/mips/mips.igen
index 7cb9d10..cd96766 100644
--- a/sim/mips/mips.igen
+++ b/sim/mips/mips.igen
@@ -144,6 +144,70 @@
// Helper:
//
+// Check that a 32-bit register value is properly sign-extended.
+// (See NotWordValue in ISA spec.)
+//
+
+:function:::int:not_word_value:unsigned_word value
+*mipsI:
+*mipsII:
+*mipsIII:
+*mipsIV:
+*mipsV:
+*vr4100:
+*vr5000:
+*r3900:
+{
+ /* For historical simulator compatibility (until documentation is
+ found that makes these operations unpredictable on some of these
+ architectures), this check never returns true. */
+ return 0;
+}
+
+:function:::int:not_word_value:unsigned_word value
+*mips32:
+{
+ /* On MIPS32, since registers are 32-bits, there's no check to be done. */
+ return 0;
+}
+
+:function:::int:not_word_value:unsigned_word value
+*mips64:
+{
+ return ((value >> 32) != (value & 0x80000000 ? 0xFFFFFFFF : 0));
+}
+
+
+// Helper:
+//
+// Handle UNPREDICTABLE operation behaviour. The goal here is to prevent
+// theoretically portable code which invokes non-portable behaviour from
+// running with no indication of the portability issue.
+// (See definition of UNPREDICTABLE in ISA spec.)
+//
+
+:function:::void:unpredictable:
+*mipsI:
+*mipsII:
+*mipsIII:
+*mipsIV:
+*mipsV:
+*vr4100:
+*vr5000:
+*r3900:
+{
+}
+
+:function:::void:unpredictable:
+*mips32:
+*mips64:
+{
+ unpredictable_action (CPU, CIA);
+}
+
+
+// Helper:
+//
// Check that an access to a HI/LO register meets timing requirements
//
// The following requirements exist:
@@ -340,6 +404,8 @@
*vr5000:
*r3900:
{
+ if (NotWordValue (GPR[RS]) || NotWordValue (GPR[RT]))
+ Unpredictable ();
TRACE_ALU_INPUT2 (GPR[RS], GPR[RT]);
{
ALU32_BEGIN (GPR[RS]);
@@ -364,6 +430,8 @@
*vr5000:
*r3900:
{
+ if (NotWordValue (GPR[RS]))
+ Unpredictable ();
TRACE_ALU_INPUT2 (GPR[RS], EXTEND16 (IMMEDIATE));
{
ALU32_BEGIN (GPR[RS]);
@@ -377,6 +445,8 @@
:function:::void:do_addiu:int rs, int rt, unsigned16 immediate
{
+ if (NotWordValue (GPR[rs]))
+ Unpredictable ();
TRACE_ALU_INPUT2 (GPR[rs], EXTEND16 (immediate));
GPR[rt] = EXTEND32 (GPR[rs] + EXTEND16 (immediate));
TRACE_ALU_RESULT (GPR[rt]);
@@ -402,6 +472,8 @@
:function:::void:do_addu:int rs, int rt, int rd
{
+ if (NotWordValue (GPR[rs]) || NotWordValue (GPR[rt]))
+ Unpredictable ();
TRACE_ALU_INPUT2 (GPR[rs], GPR[rt]);
GPR[rd] = EXTEND32 (GPR[rs] + GPR[rt]);
TRACE_ALU_RESULT (GPR[rd]);
@@ -558,6 +630,8 @@
{
address_word offset = EXTEND16 (OFFSET) << 2;
check_branch_bug ();
+ if (RS == 31)
+ Unpredictable ();
RA = (CIA + 8);
if ((signed_word) GPR[RS] >= 0)
{
@@ -582,6 +656,8 @@
{
address_word offset = EXTEND16 (OFFSET) << 2;
check_branch_bug ();
+ if (RS == 31)
+ Unpredictable ();
RA = (CIA + 8);
/* NOTE: The branch occurs AFTER the next instruction has been
executed */
@@ -762,6 +838,8 @@
{
address_word offset = EXTEND16 (OFFSET) << 2;
check_branch_bug ();
+ if (RS == 31)
+ Unpredictable ();
RA = (CIA + 8);
/* NOTE: The branch occurs AFTER the next instruction has been
executed */
@@ -788,6 +866,8 @@
{
address_word offset = EXTEND16 (OFFSET) << 2;
check_branch_bug ();
+ if (RS == 31)
+ Unpredictable ();
RA = (CIA + 8);
if ((signed_word) GPR[RS] < 0)
{
@@ -926,6 +1006,8 @@
unsigned32 i, mask;
if (RT != RD)
Unpredictable ();
+ if (NotWordValue (GPR[RS]))
+ Unpredictable ();
TRACE_ALU_INPUT1 (GPR[RS]);
for (mask = ((unsigned32)1<<31), i = 0; i < 32; ++i)
{
@@ -948,6 +1030,8 @@
unsigned32 i, mask;
if (RT != RD)
Unpredictable ();
+ if (NotWordValue (GPR[RS]))
+ Unpredictable ();
TRACE_ALU_INPUT1 (GPR[RS]);
for (mask = ((unsigned32)1<<31), i = 0; i < 32; ++i)
{
@@ -2099,6 +2183,8 @@
{
signed64 temp;
check_mult_hilo (SD_, HIHISTORY, LOHISTORY);
+ if (NotWordValue (GPR[RS]) || NotWordValue (GPR[RT]))
+ Unpredictable ();
TRACE_ALU_INPUT2 (GPR[RS], GPR[RT]);
temp = (U8_4 (VL4_8 (HI), VL4_8 (LO))
+ ((signed64) EXTEND32 (GPR[RT]) * (signed64) EXTEND32 (GPR[RS])));
@@ -2116,6 +2202,8 @@
{
unsigned64 temp;
check_mult_hilo (SD_, HIHISTORY, LOHISTORY);
+ if (NotWordValue (GPR[RS]) || NotWordValue (GPR[RT]))
+ Unpredictable ();
TRACE_ALU_INPUT2 (GPR[RS], GPR[RT]);
temp = (U8_4 (VL4_8 (HI), VL4_8 (LO))
+ ((unsigned64) VL4_8 (GPR[RS]) * (unsigned64) VL4_8 (GPR[RT])));
@@ -2212,6 +2300,8 @@
{
signed64 temp;
check_mult_hilo (SD_, HIHISTORY, LOHISTORY);
+ if (NotWordValue (GPR[RS]) || NotWordValue (GPR[RT]))
+ Unpredictable ();
TRACE_ALU_INPUT2 (GPR[RS], GPR[RT]);
temp = (U8_4 (VL4_8 (HI), VL4_8 (LO))
- ((signed64) EXTEND32 (GPR[RT]) * (signed64) EXTEND32 (GPR[RS])));
@@ -2229,6 +2319,8 @@
{
unsigned64 temp;
check_mult_hilo (SD_, HIHISTORY, LOHISTORY);
+ if (NotWordValue (GPR[RS]) || NotWordValue (GPR[RT]))
+ Unpredictable ();
TRACE_ALU_INPUT2 (GPR[RS], GPR[RT]);
temp = (U8_4 (VL4_8 (HI), VL4_8 (LO))
- ((unsigned64) VL4_8 (GPR[RS]) * (unsigned64) VL4_8 (GPR[RT])));
@@ -2283,6 +2375,8 @@
*mips64:
{
signed64 prod;
+ if (NotWordValue (GPR[RS]) || NotWordValue (GPR[RT]))
+ Unpredictable ();
TRACE_ALU_INPUT2 (GPR[RS], GPR[RT]);
prod = (((signed64)(signed32) GPR[RS])
* ((signed64)(signed32) GPR[RT]));
@@ -2296,6 +2390,8 @@
{
signed64 prod;
check_mult_hilo (SD_, HIHISTORY, LOHISTORY);
+ if (NotWordValue (GPR[rs]) || NotWordValue (GPR[rt]))
+ Unpredictable ();
TRACE_ALU_INPUT2 (GPR[rs], GPR[rt]);
prod = (((signed64)(signed32) GPR[rs])
* ((signed64)(signed32) GPR[rt]));
@@ -2335,6 +2431,8 @@
{
unsigned64 prod;
check_mult_hilo (SD_, HIHISTORY, LOHISTORY);
+ if (NotWordValue (GPR[rs]) || NotWordValue (GPR[rt]))
+ Unpredictable ();
TRACE_ALU_INPUT2 (GPR[rs], GPR[rt]);
prod = (((unsigned64)(unsigned32) GPR[rs])
* ((unsigned64)(unsigned32) GPR[rt]));
@@ -2893,6 +2991,8 @@
:function:::void:do_sra:int rt, int rd, int shift
{
signed32 temp = (signed32) GPR[rt] >> shift;
+ if (NotWordValue (GPR[rt]))
+ Unpredictable ();
TRACE_ALU_INPUT2 (GPR[rt], shift);
GPR[rd] = EXTEND32 (temp);
TRACE_ALU_RESULT (GPR[rd]);
@@ -2920,6 +3020,8 @@
{
int s = MASKED (GPR[rs], 4, 0);
signed32 temp = (signed32) GPR[rt] >> s;
+ if (NotWordValue (GPR[rt]))
+ Unpredictable ();
TRACE_ALU_INPUT2 (GPR[rt], s);
GPR[rd] = EXTEND32 (temp);
TRACE_ALU_RESULT (GPR[rd]);
@@ -2946,6 +3048,8 @@
:function:::void:do_srl:int rt, int rd, int shift
{
unsigned32 temp = (unsigned32) GPR[rt] >> shift;
+ if (NotWordValue (GPR[rt]))
+ Unpredictable ();
TRACE_ALU_INPUT2 (GPR[rt], shift);
GPR[rd] = EXTEND32 (temp);
TRACE_ALU_RESULT (GPR[rd]);
@@ -2972,6 +3076,8 @@
{
int s = MASKED (GPR[rs], 4, 0);
unsigned32 temp = (unsigned32) GPR[rt] >> s;
+ if (NotWordValue (GPR[rt]))
+ Unpredictable ();
TRACE_ALU_INPUT2 (GPR[rt], s);
GPR[rd] = EXTEND32 (temp);
TRACE_ALU_RESULT (GPR[rd]);
@@ -3007,6 +3113,8 @@
*vr5000:
*r3900:
{
+ if (NotWordValue (GPR[RS]) || NotWordValue (GPR[RT]))
+ Unpredictable ();
TRACE_ALU_INPUT2 (GPR[RS], GPR[RT]);
{
ALU32_BEGIN (GPR[RS]);
@@ -3019,6 +3127,8 @@
:function:::void:do_subu:int rs, int rt, int rd
{
+ if (NotWordValue (GPR[rs]) || NotWordValue (GPR[rt]))
+ Unpredictable ();
TRACE_ALU_INPUT2 (GPR[rs], GPR[rt]);
GPR[rd] = EXTEND32 (GPR[rs] - GPR[rt]);
TRACE_ALU_RESULT (GPR[rd]);