Optimize arrays of register indexes in syscall_enter

* syscall.c (syscall_enter) [BFIN]: Make register no array "static const".
  [SH]: Make register no array "const", pre-multiply it by 4.
  [SH64]: Make register no array "const".
  [X86_64]: Make register no array "const", pre-multiply it by 8.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>

diff --git a/syscall.c b/syscall.c
index 83380af3db9ce1e97762ddbb06924657944d101b..d495ae500831052dfd8e000314419c943f6db7f3 100644 (file)
--- a/syscall.c
+++ b/syscall.c
@@ -2121,7 +2121,7 @@ syscall_enter(struct tcb *tcp)
        tcp->u_arg[5] = regs.r3;
 # elif defined(BFIN)
        int i;
-       int argreg[] = {PT_R0, PT_R1, PT_R2, PT_R3, PT_R4, PT_R5};
+       static const int argreg[] = { PT_R0, PT_R1, PT_R2, PT_R3, PT_R4, PT_R5 };
 
        if (tcp->scno >= 0 && tcp->scno < nsyscalls && sysent[tcp->scno].nargs != -1)
                tcp->u_nargs = sysent[tcp->scno].nargs;
@@ -2133,20 +2133,20 @@ syscall_enter(struct tcb *tcp)
                        return -1;
 # elif defined(SH)
        int i;
-       static int syscall_regs[] = {
-               REG_REG0+4, REG_REG0+5, REG_REG0+6, REG_REG0+7,
-               REG_REG0, REG_REG0+1, REG_REG0+2
+       static const int syscall_regs[] = {
+               4 * (REG_REG0+4), 4 * (REG_REG0+5), 4 * (REG_REG0+6), 4 * (REG_REG0+7),
+               4 * (REG_REG0  ), 4 * (REG_REG0+1), 4 * (REG_REG0+2)
        };
 
        tcp->u_nargs = sysent[tcp->scno].nargs;
        for (i = 0; i < tcp->u_nargs; i++) {
-               if (upeek(tcp, 4 * syscall_regs[i], &tcp->u_arg[i]) < 0)
+               if (upeek(tcp, syscall_regs[i], &tcp->u_arg[i]) < 0)
                        return -1;
        }
 # elif defined(SH64)
        int i;
        /* Registers used by SH5 Linux system calls for parameters */
-       static int syscall_regs[] = { 2, 3, 4, 5, 6, 7 };
+       static const int syscall_regs[] = { 2, 3, 4, 5, 6, 7 };
 
        /*
         * TODO: should also check that the number of arguments encoded
@@ -2163,9 +2163,9 @@ syscall_enter(struct tcb *tcp)
        }
 # elif defined(X86_64)
        int i;
-       static int argreg[SUPPORTED_PERSONALITIES][MAX_ARGS] = {
-               {RDI,RSI,RDX,R10,R8,R9},        /* x86-64 ABI */
-               {RBX,RCX,RDX,RSI,RDI,RBP}       /* i386 ABI */
+       static const int argreg[SUPPORTED_PERSONALITIES][MAX_ARGS] = {
+               { 8 * RDI, 8 * RSI, 8 * RDX, 8 * R10, 8 * R8 , 8 * R9  }, /* x86-64 ABI */
+               { 8 * RBX, 8 * RCX, 8 * RDX, 8 * RSI, 8 * RDI, 8 * RBP }  /* i386 ABI */
        };
 
        if (tcp->scno >= 0 && tcp->scno < nsyscalls && sysent[tcp->scno].nargs != -1)
@@ -2173,7 +2173,7 @@ syscall_enter(struct tcb *tcp)
        else
                tcp->u_nargs = MAX_ARGS;
        for (i = 0; i < tcp->u_nargs; i++) {
-               if (upeek(tcp, argreg[current_personality][i]*8, &tcp->u_arg[i]) < 0)
+               if (upeek(tcp, argreg[current_personality][i], &tcp->u_arg[i]) < 0)
                        return -1;
        }
 # elif defined(MICROBLAZE)
@@ -2190,7 +2190,7 @@ syscall_enter(struct tcb *tcp)
        int i;
        static const int crisregs[] = {
                4*PT_ORIG_R10, 4*PT_R11, 4*PT_R12,
-               4*PT_R13, 4*PT_MOF, 4*PT_SRP
+               4*PT_R13     , 4*PT_MOF, 4*PT_SRP
        };
 
        if (tcp->scno >= 0 && tcp->scno < nsyscalls)