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Diffstat (limited to 'gdb/config/convex/Convex.notes')
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diff --git a/gdb/config/convex/Convex.notes b/gdb/config/convex/Convex.notes deleted file mode 100644 index 828778c..0000000 --- a/gdb/config/convex/Convex.notes +++ /dev/null @@ -1,164 +0,0 @@ -@c OBSOLETE -@c OBSOLETE @node Convex,,, Top -@c OBSOLETE @appendix Convex-specific info -@c OBSOLETE @cindex Convex notes -@c OBSOLETE -@c OBSOLETE Scalar registers are 64 bits long, which is a pain since -@c OBSOLETE left half of an S register frequently contains noise. -@c OBSOLETE Therefore there are two ways to obtain the value of an S register. -@c OBSOLETE -@c OBSOLETE @table @kbd -@c OBSOLETE @item $s0 -@c OBSOLETE returns the low half of the register as an int -@c OBSOLETE -@c OBSOLETE @item $S0 -@c OBSOLETE returns the whole register as a long long -@c OBSOLETE @end table -@c OBSOLETE -@c OBSOLETE You can print the value in floating point by using @samp{p/f $s0} or @samp{p/f $S0} -@c OBSOLETE to print a single or double precision value. -@c OBSOLETE -@c OBSOLETE @cindex vector registers -@c OBSOLETE Vector registers are handled similarly, with @samp{$V0} denoting the whole -@c OBSOLETE 64-bit register and @kbd{$v0} denoting the 32-bit low half; @samp{p/f $v0} -@c OBSOLETE or @samp{p/f $V0} can be used to examine the register in floating point. -@c OBSOLETE The length of the vector registers is taken from @samp{$vl}. -@c OBSOLETE -@c OBSOLETE Individual elements of a vector register are denoted in the obvious way; -@c OBSOLETE @samp{print $v3[9]} prints the tenth element of register @kbd{v3}, and -@c OBSOLETE @samp{set $v3[9] = 1234} alters it. -@c OBSOLETE -@c OBSOLETE @kbd{$vl} and @kbd{$vs} are int, and @kbd{$vm} is an int vector. -@c OBSOLETE Elements of @kbd{$vm} can't be assigned to. -@c OBSOLETE -@c OBSOLETE @cindex communication registers -@c OBSOLETE @kindex info comm-registers -@c OBSOLETE Communication registers have names @kbd{$C0 .. $C63}, with @kbd{$c0 .. $c63} -@c OBSOLETE denoting the low-order halves. @samp{info comm-registers} will print them -@c OBSOLETE all out, and tell which are locked. (A communication register is -@c OBSOLETE locked when a value is sent to it, and unlocked when the value is -@c OBSOLETE received.) Communication registers are, of course, global to all -@c OBSOLETE threads, so it does not matter what the currently selected thread is. -@c OBSOLETE @samp{info comm-reg @var{name}} prints just that one communication -@c OBSOLETE register; @samp{name} may also be a communication register number -@c OBSOLETE @samp{nn} or @samp{0xnn}. -@c OBSOLETE @samp{info comm-reg @var{address}} prints the contents of the resource -@c OBSOLETE structure at that address. -@c OBSOLETE -@c OBSOLETE @kindex info psw -@c OBSOLETE The command @samp{info psw} prints the processor status word @kbd{$ps} -@c OBSOLETE bit by bit. -@c OBSOLETE -@c OBSOLETE @kindex set base -@c OBSOLETE GDB normally prints all integers in base 10, but the leading -@c OBSOLETE @kbd{0x80000000} of pointers is intolerable in decimal, so the default -@c OBSOLETE output radix has been changed to try to print addresses appropriately. -@c OBSOLETE The @samp{set base} command can be used to change this. -@c OBSOLETE -@c OBSOLETE @table @code -@c OBSOLETE @item set base 10 -@c OBSOLETE Integer values always print in decimal. -@c OBSOLETE -@c OBSOLETE @item set base 16 -@c OBSOLETE Integer values always print in hex. -@c OBSOLETE -@c OBSOLETE @item set base -@c OBSOLETE Go back to the initial state, which prints integer values in hex if they -@c OBSOLETE look like pointers (specifically, if they start with 0x8 or 0xf in the -@c OBSOLETE stack), otherwise in decimal. -@c OBSOLETE @end table -@c OBSOLETE -@c OBSOLETE @kindex set pipeline -@c OBSOLETE When an exception such as a bus error or overflow happens, usually the PC -@c OBSOLETE is several instructions ahead by the time the exception is detected. -@c OBSOLETE The @samp{set pipe} command will disable this. -@c OBSOLETE -@c OBSOLETE @table @code -@c OBSOLETE @item set pipeline off -@c OBSOLETE Forces serial execution of instructions; no vector chaining and no -@c OBSOLETE scalar instruction overlap. With this, exceptions are detected with -@c OBSOLETE the PC pointing to the instruction after the one in error. -@c OBSOLETE -@c OBSOLETE @item set pipeline on -@c OBSOLETE Returns to normal, fast, execution. This is the default. -@c OBSOLETE @end table -@c OBSOLETE -@c OBSOLETE @cindex parallel -@c OBSOLETE In a parallel program, multiple threads may be executing, each -@c OBSOLETE with its own registers, stack, and local memory. When one of them -@c OBSOLETE hits a breakpoint, that thread is selected. Other threads do -@c OBSOLETE not run while the thread is in the breakpoint. -@c OBSOLETE -@c OBSOLETE @kindex 1cont -@c OBSOLETE The selected thread can be single-stepped, given signals, and so -@c OBSOLETE on. Any other threads remain stopped. When a @samp{cont} command is given, -@c OBSOLETE all threads are resumed. To resume just the selected thread, use -@c OBSOLETE the command @samp{1cont}. -@c OBSOLETE -@c OBSOLETE @kindex thread -@c OBSOLETE The @samp{thread} command will show the active threads and the -@c OBSOLETE instruction they are about to execute. The selected thread is marked -@c OBSOLETE with an asterisk. The command @samp{thread @var{n}} will select thread @var{n}, -@c OBSOLETE shifting the debugger's attention to it for single-stepping, -@c OBSOLETE registers, local memory, and so on. -@c OBSOLETE -@c OBSOLETE @kindex info threads -@c OBSOLETE The @samp{info threads} command will show what threads, if any, have -@c OBSOLETE invisibly hit breakpoints or signals and are waiting to be noticed. -@c OBSOLETE -@c OBSOLETE @kindex set parallel -@c OBSOLETE The @samp{set parallel} command controls how many threads can be active. -@c OBSOLETE -@c OBSOLETE @table @code -@c OBSOLETE @item set parallel off -@c OBSOLETE One thread. Requests by the program that other threads join in -@c OBSOLETE (spawn and pfork instructions) do not cause other threads to start up. -@c OBSOLETE This does the same thing as the @samp{limit concurrency 1} command. -@c OBSOLETE -@c OBSOLETE @item set parallel fixed -@c OBSOLETE All CPUs are assigned to your program whenever it runs. When it -@c OBSOLETE executes a pfork or spawn instruction, it begins parallel execution -@c OBSOLETE immediately. This does the same thing as the @samp{mpa -f} command. -@c OBSOLETE -@c OBSOLETE @item set parallel on -@c OBSOLETE One or more threads. Spawn and pfork cause CPUs to join in when and if -@c OBSOLETE they are free. This is the default. It is very good for system -@c OBSOLETE throughput, but not very good for finding bugs in parallel code. If you -@c OBSOLETE suspect a bug in parallel code, you probably want @samp{set parallel fixed.} -@c OBSOLETE @end table -@c OBSOLETE -@c OBSOLETE @subsection Limitations -@c OBSOLETE -@c OBSOLETE WARNING: Convex GDB evaluates expressions in long long, because S -@c OBSOLETE registers are 64 bits long. However, GDB expression semantics are not -@c OBSOLETE exactly C semantics. This is a bug, strictly speaking, but it's not one I -@c OBSOLETE know how to fix. If @samp{x} is a program variable of type int, then it -@c OBSOLETE is also type int to GDB, but @samp{x + 1} is long long, as is @samp{x + y} -@c OBSOLETE or any other expression requiring computation. So is the expression -@c OBSOLETE @samp{1}, or any other constant. You only really have to watch out for -@c OBSOLETE calls. The innocuous expression @samp{list_node (0x80001234)} has an -@c OBSOLETE argument of type long long. You must explicitly cast it to int. -@c OBSOLETE -@c OBSOLETE It is not possible to continue after an uncaught fatal signal by using -@c OBSOLETE @samp{signal 0}, @samp{return}, @samp{jump}, or anything else. The difficulty is with -@c OBSOLETE Unix, not GDB. -@c OBSOLETE -@c OBSOLETE I have made no big effort to make such things as single-stepping a -@c OBSOLETE @kbd{join} instruction do something reasonable. If the program seems to -@c OBSOLETE hang when doing this, type @kbd{ctrl-c} and @samp{cont}, or use -@c OBSOLETE @samp{thread} to shift to a live thread. Single-stepping a @kbd{spawn} -@c OBSOLETE instruction apparently causes new threads to be born with their T bit set; -@c OBSOLETE this is not handled gracefully. When a thread has hit a breakpoint, other -@c OBSOLETE threads may have invisibly hit the breakpoint in the background; if you -@c OBSOLETE clear the breakpoint gdb will be surprised when threads seem to continue -@c OBSOLETE to stop at it. All of these situations produce spurious signal 5 traps; -@c OBSOLETE if this happens, just type @samp{cont}. If it becomes a nuisance, use -@c OBSOLETE @samp{handle 5 nostop}. (It will ask if you are sure. You are.) -@c OBSOLETE -@c OBSOLETE There is no way in GDB to store a float in a register, as with -@c OBSOLETE @kbd{set $s0 = 3.1416}. The identifier @kbd{$s0} denotes an integer, -@c OBSOLETE and like any C expression which assigns to an integer variable, the -@c OBSOLETE right-hand side is casted to type int. If you should need to do -@c OBSOLETE something like this, you can assign the value to @kbd{@{float@} ($sp-4)} -@c OBSOLETE and then do @kbd{set $s0 = $sp[-4]}. Same deal with @kbd{set $v0[69] = 6.9}. - |