Re: Today's compiling adventure

Message-ID: <43C69F48.7090600@ftml.net>

p4raw-id: //depot/perl@26807

1 files changed, 355 insertions, 0 deletions

diff --git a/mpeix/mpeix_setjmp.c b/mpeix/mpeix_setjmp.c
new file mode 100644
index 0000000000..955fe03d15
--- /dev/null
+++ b/mpeix/mpeix_setjmp.c
@@ -0,0 +1,355 @@
+/* Workaround for CR JAGab60546 setjmp/longjmp and
+   JAGad55982 sigsetjmp/siglongjmp from shared libraries. */
+
+/*
+  * tabstop=4
+  *
+  * _setjmp/setjmp/sigsetjmp and
+  *_longjmp/longjmp/siglongjmp.
+  *
+  * Written by Mark Klein, 10 October, 2000
+  * Updated for gcc 3.x 6 October, 2005
+  *
+  * These routines are GCC specific and MUST BE COMPILED
+  * WITH -O2
+  *
+  * The existing setjmp/longjmp code in both libc.a and XL.PUB.SYS
+  * are not SR4 aware and cause problems when working with shared
+  * libraries (XLs), especially when executing a longjmp between
+  * XLs. This code preserves SR4 and will successfully handle
+  * a cross space longjmp. However, the setjmp code must be
+  * bound into each XL from which it will be called as well as
+  * being bound into the main program.
+  */
+
+/*
+  * The following macro takes the contents of the jmpbuf and
+  * restores the registers from them. There is other code
+  * elsewhere that ensures that __jmpbuf is %r26 at this
+  * point in time. If it becomes some other register, that
+  * register must be the last restored. At the end will
+  * be a branch external that will cause a cross space
+  * return if needed.
+  */
+#define RESTORE_REGS_AND_RETURN(__jmpbuf, __retval)                  \
+({                                                                   \
+         __asm__ __volatile__ (                                      \
+             "   ldw    0(%%sr0, %0), %%rp\n"                        \
+             "\t   ldw    4(%%sr0, %0), %%sp\n"                      \
+             "\t   ldw   16(%%sr0, %0), %%r3\n"                      \
+             "\t   ldw   20(%%sr0, %0), %%r4\n"                      \
+             "\t   ldw   24(%%sr0, %0), %%r5\n"                      \
+             "\t   ldw   28(%%sr0, %0), %%r6\n"                      \
+             "\t   ldw   32(%%sr0, %0), %%r7\n"                      \
+             "\t   ldw   36(%%sr0, %0), %%r8\n"                      \
+             "\t   ldw   40(%%sr0, %0), %%r9\n"                      \
+             "\t   ldw   44(%%sr0, %0), %%r10\n"                     \
+             "\t   ldw   48(%%sr0, %0), %%r11\n"                     \
+             "\t   ldw   52(%%sr0, %0), %%r12\n"                     \
+             "\t   ldw   56(%%sr0, %0), %%r13\n"                     \
+             "\t   ldw   60(%%sr0, %0), %%r14\n"                     \
+             "\t   ldw   64(%%sr0, %0), %%r15\n"                     \
+             "\t   ldw   68(%%sr0, %0), %%r16\n"                     \
+             "\t   ldw   72(%%sr0, %0), %%r17\n"                     \
+             "\t   ldw   76(%%sr0, %0), %%r18\n"                     \
+             "\t   ldw   80(%%sr0, %0), %%r19\n"                     \
+             "\t   ldw   84(%%sr0, %0), %%r20\n"                     \
+             "\t   ldw   88(%%sr0, %0), %%r21\n"                     \
+             "\t   ldw   92(%%sr0, %0), %%r22\n"                     \
+             "\t   ldw   96(%%sr0, %0), %%r23\n"                     \
+             "\t   ldw  100(%%sr0, %0), %%r24\n"                     \
+             "\t   ldw  104(%%sr0, %0), %%r25\n"                     \
+             "\t   ldw  112(%%sr0, %0), %%r27\n"                     \
+             "\t   ldw  116(%%sr0, %0), %%r1\n"                      \
+             "\t   mtsp %%r1, %%sr3\n"                               \
+             "\t   ldw  120(%%sr0, %0), %%r1\n"                      \
+             "\t   mtsp %%r1, %%sr1\n"                               \
+             "\t   or,<>   %%r0, %1, %%r0\n"                         \
+             "\t     ldi 1, %%r28\n"                                 \
+             "\t   ldw  108(%%sr0, %0), %%r26\n"                     \
+             "\t   be       0(%%sr1, %%rp)\n"                        \
+             "\t   mtsp %%r1, %%sr4\n"                               \
+                 : \
+                 : "r" (__jmpbuf),                                   \
+                   "r" (__retval));                                  \
+})
+
+/*
+  * The following macro extracts the signal mask
+  * from  __jmpbuf from the 3rd and 4th words and
+  * if non-zero, calls sigprocmask with that value
+  * to set the signal mask. This macro is usually
+  * invoked before the registers are restored in
+  * the longjmp routines and it can clobber things
+  * without needing to spill them as a result.
+  * A quick frame is built before making the
+  * call and cut back just afterwards.
+  * The ldi 2, %r26 is actually SIG_SETMASK from
+  * /usr/include/signal.h.
+  */
+#define RESTORE_SIGNAL_MASK(__jmpbuf)                                \
+({                                                                   \
+   __asm__ __volatile__ (                                            \
+              "  ldw 8(%0), %%r26\n"                                 \
+              "\t  comibt,=,n 0,%%r26,.+36\n"                        \
+              "\t    ldo 64(%%sp), %%sp\n"                           \
+              "\t    stw %0, -28(%%sp)\n"                            \
+              "\t    ldi 0, %%r24\n"                                 \
+              "\t    ldo 8(%0), %%r25\n"                             \
+              "\t    .import sigprocmask,code\n"                     \
+              "\t    bl sigprocmask,%%rp\n"                          \
+              "\t    ldi 2, %%r26\n"                                 \
+              "\t    ldw -28(%%sr0, %%sp), %0\n"                     \
+              "\t    ldo -64(%%sp), %%sp\n"                          \
+                     :                                               \
+                     : "r" (__jmpbuf));                              \
+})
+
+/*
+  * This macro saves the current contents of the
+  * registers to __jmpbuf. Note that __jmpbuf is
+  * guaranteed elsewhere to be in %r26. We do not
+  * want it spilled, nor do we want a new frame
+  * built.
+  */
+#define SAVE_REGS(__jmpbuf)                                          \
+({                                                                   \
+   __asm__ __volatile__ (                                            \
+              "  stw %%rp,     0(%%sr0, %0)\n"                       \
+              "\t  stw %%sp,     4(%%sr0, %0)\n"                     \
+              "\t  stw %%r0,     8(%%sr0, %0)\n"                     \
+              "\t  stw %%r3,    16(%%sr0, %0)\n"                     \
+              "\t  stw %%r4,    20(%%sr0, %0)\n"                     \
+              "\t  stw %%r5,    24(%%sr0, %0)\n"                     \
+              "\t  stw %%r6,    28(%%sr0, %0)\n"                     \
+              "\t  stw %%r7,    32(%%sr0, %0)\n"                     \
+              "\t  stw %%r8,    36(%%sr0, %0)\n"                     \
+              "\t  stw %%r9,    40(%%sr0, %0)\n"                     \
+              "\t  stw %%r10,   44(%%sr0, %0)\n"                     \
+              "\t  stw %%r11,   48(%%sr0, %0)\n"                     \
+              "\t  stw %%r12,   52(%%sr0, %0)\n"                     \
+              "\t  stw %%r13,   56(%%sr0, %0)\n"                     \
+              "\t  stw %%r14,   60(%%sr0, %0)\n"                     \
+              "\t  stw %%r15,   64(%%sr0, %0)\n"                     \
+              "\t  stw %%r16,   68(%%sr0, %0)\n"                     \
+              "\t  stw %%r17,   72(%%sr0, %0)\n"                     \
+              "\t  stw %%r18,   76(%%sr0, %0)\n"                     \
+              "\t  stw %%r19,   80(%%sr0, %0)\n"                     \
+              "\t  stw %%r20,   84(%%sr0, %0)\n"                     \
+              "\t  stw %%r21,   88(%%sr0, %0)\n"                     \
+              "\t  stw %%r22,   92(%%sr0, %0)\n"                     \
+              "\t  stw %%r23,   96(%%sr0, %0)\n"                     \
+              "\t  stw %%r24,  100(%%sr0, %0)\n"                     \
+              "\t  stw %%r25,  104(%%sr0, %0)\n"                     \
+              "\t  stw %%r26,  108(%%sr0, %0)\n"                     \
+              "\t  stw %%r27,  112(%%sr0, %0)\n"                     \
+              "\t  mfsp %%sr3, %%r1\n"                               \
+              "\t  stw %%r1,   116(%%sr0, %0)\n"                     \
+              "\t  mfsp %%sr4, %%r1\n"                               \
+              "\t  stw %%r1,   120(%%sr0, %0)\n"                     \
+                   :                                                 \
+                   : "r" (__jmpbuf));                                \
+})
+
+/*
+  * This macro will save the signal mask to the
+  * __jmpbuf if __savemask is non-zero. By this
+  * point in time, the other resisters have been
+  * saved into the __jmpbuf.
+  * The ldi 0, %r26 is actually SIG_BLOCK from
+  * /usr/include/signal.h. Since the block is
+  * an OR of the bits, this does not change the
+  * mask, but returns it into the double word at
+  * the address in %r24.
+  */
+#define SAVE_SIGNAL_MASK(__jmpbuf,__savemask)                        \
+({                                                                   \
+   __asm__ __volatile__ (                                            \
+              "  comibt,=,n 0,%1,.+36\n"                             \
+              "\t    stw %%rp, -20(%%sr0, %%sp)\n"                   \
+              "\t    ldo 64(%%sp), %%sp\n"                           \
+              "\t    ldo 8(%0), %%r24\n"                             \
+              "\t    ldi 0, %%r25\n"                                 \
+              "\t    .import sigprocmask,code\n"                     \
+              "\t    bl sigprocmask,%%rp\n"                          \
+              "\t    ldi 0, %%r26\n"                                 \
+              "\t    ldo -64(%%sp), %%sp\n"                          \
+              "\t    ldw -20(%%sr0, %%sp), %%rp\n"                   \
+                     :                                               \
+                     : "r" (__jmpbuf),                               \
+                       "r" (__savemask));                            \
+})
+
+/*
+  * Construct a jump buffer and unconditionally save
+  * the signal mask. Return a 0 unconditinoally.
+  * Care is taken here and in the macros to assume
+  * the __jumpbuf is in %r26 and that the return
+  * value will be in %r28. It is done this way to
+  * prevent a frame from being built and any registers
+  * from being spilled.
+  */
+int setjmp(register void *jmpbuf)
+{
+   register int __jmpbuf asm ("%r26");
+
+   SAVE_REGS(__jmpbuf);
+   SAVE_SIGNAL_MASK(__jmpbuf, 1);
+   return 0;
+}
+
+/*
+  * Construct a jump buffer but do not save the
+  * signal mask.
+  */
+int _setjmp(register void *jmpbuf)
+{
+   register int __jmpbuf asm ("%r26");
+
+   SAVE_REGS(__jmpbuf);
+   return 0;
+}
+
+/*
+  * Construct a jump buffer and conditionally save
+  * the signal mask. The mask is saved if the
+  * savemask parameter is non-zero.
+  */
+int sigsetjmp(register void *jmpbuf, register int savemask)
+{
+   register int __jmpbuf   asm ("%r26");
+   register int __savemask asm ("%r25");
+
+   SAVE_REGS(__jmpbuf);
+   SAVE_SIGNAL_MASK(__jmpbuf, __savemask);
+   return 0;
+}
+
+/*
+  * Return to the location established in the jmpbuf,
+  * and place the value in i2 in %r28. Registers
+  * %r4 and %r5 are co-opted to save the address and
+  * value of jmpbuf and the return value. The signal
+  * mask is re-established if needed, then the
+  * address of jmpbuf and value of retval are placed
+  * into %r26 and %r28 correspondingly. This routine
+  * will never return to its caller and the stack
+  * will be cut back to whatever exists in the jmpbuf.
+  */
+void longjmp(register void *jmpbuf, register int i2)
+{
+   register int __jmpbuf        asm ("%r26");
+   register int __retval        asm ("%r28");
+
+   __asm__ __volatile__ (
+              "  copy %0, %%r4\n"
+              "\t  copy %1, %%r5\n"
+                     :
+                     : "r" (jmpbuf),
+                       "r" (i2));
+
+   RESTORE_SIGNAL_MASK (__jmpbuf);
+
+   __asm__ __volatile__ (
+              "  copy %%r4, %0\n"
+              "\t  copy %%r5, %1\n"
+                     : "=r" (__jmpbuf),
+                       "=r" (__retval));
+
+   RESTORE_REGS_AND_RETURN (__jmpbuf, __retval);
+}
+
+/*
+  * Return to the location established in the jmpbuf,
+  * but do not restore the signal mask.
+  */
+void _longjmp(register void *jmpbuf, register int i2)
+{
+   register int __retval         asm ("%r28");
+   register int __jmpbuf         asm ("%r26");
+
+   __jmpbuf = (int)jmpbuf;
+   __retval = i2;
+
+   RESTORE_REGS_AND_RETURN (__jmpbuf, __retval);
+}
+
+/*
+  * Return to the location establsihed in the jmpbuf,
+  * and conditionally re-establish the signal mask.
+  */
+void siglongjmp(register void *jmpbuf, register int i2)
+{
+   register int __jmpbuf        asm ("%r26");
+   register int __retval        asm ("%r28");
+
+   __asm__ __volatile__ (
+              "  copy %0, %%r4\n"
+              "\t  copy %1, %%r5\n"
+                     :
+                     : "r" (jmpbuf),
+                       "r" (i2));
+
+   RESTORE_SIGNAL_MASK (__jmpbuf);
+
+   __asm__ __volatile__ (
+              "  copy %%r4, %0\n"
+              "\t  copy %%r5, %1\n"
+                     : "=r" (__jmpbuf),
+                       "=r" (__retval));
+
+   RESTORE_REGS_AND_RETURN (__jmpbuf, __retval);
+}
+
+#ifdef TEST
+int buf1[50];
+int buf2[50];
+
+foo() {
+   printf("In routine foo(). Doing Longjmp.\n");
+   longjmp(buf1, 123);
+   printf("This is in foo after the longjmp() call. Should not reach here.\n");
+}
+
+bar(int ret) {
+   printf("In routine bar(%d). Doing siglongjmp.\n",ret);
+   siglongjmp(buf2, ret);
+   printf("This is in bar after the siglongjmp() call. Should not reach here.\n");
+}
+
+main() {
+   int i;
+   if ((i = setjmp(buf1)))
+     {
+           printf("This is the return from the longjmp. i: %d\n",i);
+         }
+   else
+     {
+           printf("Jump buffer established, i: %d. Calling foo()\n",i);
+           foo();
+           printf("This is in main after the foo() call. Should not reach here.\n ");
+         }
+
+   if ((i = sigsetjmp(buf2,0)))
+     {
+           printf("This is the return from the longjmp. i: %d\n",i);
+         }
+   else
+     {
+           printf("Jump buffer established, i: %d. Calling bar(456)\n",i);
+           bar(456);
+           printf("This is in main after the bar(456) call. Should not reach here.\n");
+         }
+
+   if ((i = sigsetjmp(buf2,1)))
+     {
+           printf("This is the return from the longjmp. i: %d\n",i);
+         }
+   else
+     {
+           printf("Jump buffer established, i: %d. Calling bar(789)\n",i);
+           bar(789);
+           printf("This is in main after the bar(789) call. Should not reach here.\n");
+         }
+}
+#endif