Tweak sparc32 longjmp to not store a dummy frame pointer onto the stack.

	* sysdeps/sparc/sparc32/__longjmp.S: Unwind in the 'thread' path
	using a normal save/restore sequence, rather than allocating a
	dummy stack frame just to store a frame pointer and restore.
	* sysdeps/unix/sysv/linux/sparc/sparc32/____longjmp_chk.S: Likewise.

diff --git a/ChangeLog b/ChangeLog
index d0352f6..73e51dc 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2012-02-20  David S. Miller  <davem@davemloft.net>
+
+       * sysdeps/sparc/sparc32/__longjmp.S: Unwind in the 'thread' path
+       using a normal save/restore sequence, rather than allocating a
+       dummy stack frame just to store a frame pointer and restore.
+       * sysdeps/unix/sysv/linux/sparc/sparc32/____longjmp_chk.S: Likewise.
+
 2012-02-21  Joseph Myers  <joseph@codesourcery.com>
 
        * manual/install.texi: Fix stray word in line-wrapped comment.

diff --git a/sysdeps/sparc/sparc32/__longjmp.S b/sysdeps/sparc/sparc32/__longjmp.S
index 7e05c95..e4caf7b 100644 (file)
--- a/sysdeps/sparc/sparc32/__longjmp.S
+++ b/sysdeps/sparc/sparc32/__longjmp.S
@@ -21,7 +21,6 @@
 #include <jmpbuf-offsets.h>
 #define ENV(base,reg) [%base + (reg * 4)]
 #define ST_FLUSH_WINDOWS 3
-#define RW_FP [%fp + 0x48]
 
 ENTRY(__longjmp)
        /* Store our arguments in global registers so we can still
@@ -54,6 +53,7 @@ LOC(loop):
         ld ENV(g1,JB_SP), %o0  /* Delay slot: extract target SP.  */
 
 LOC(thread):
+       save    %sp, -96, %sp
        /*
         * Do a "flush register windows trap".  The trap handler in the
         * kernel writes all the register windows to their stack slots, and
@@ -66,15 +66,13 @@ LOC(thread):
 #ifdef PTR_DEMANGLE
        ld      ENV(g1,JB_PC), %g5 /* Set return PC. */
        ld      ENV(g1,JB_SP), %g1 /* Set saved SP on restore below. */
-       PTR_DEMANGLE2 (%o7, %g5, %g4)
+       PTR_DEMANGLE2 (%i7, %g5, %g4)
        PTR_DEMANGLE2 (%fp, %g1, %g4)
 #else
-       ld      ENV(g1,JB_PC), %o7 /* Set return PC. */
+       ld      ENV(g1,JB_PC), %i7 /* Set return PC. */
        ld      ENV(g1,JB_SP), %fp /* Set saved SP on restore below. */
 #endif
-       sub     %fp, 64, %sp    /* Allocate a register frame. */
-       st      %g3, RW_FP      /* Set saved FP on restore below. */
-       retl
+       jmp     %i7 + 8
         restore %g2, 0, %o0    /* Restore values from above register frame. */
 
 LOC(found):

diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/____longjmp_chk.S b/sysdeps/unix/sysv/linux/sparc/sparc32/____longjmp_chk.S
index dfbf761..7246e89 100644 (file)
--- a/sysdeps/unix/sysv/linux/sparc/sparc32/____longjmp_chk.S
+++ b/sysdeps/unix/sysv/linux/sparc/sparc32/____longjmp_chk.S
@@ -20,7 +20,6 @@
 
 #define ENV(base,reg) [%base + (reg * 4)]
 #define ST_FLUSH_WINDOWS 3
-#define RW_FP [%fp + 0x48]
 
 .section .rodata.str1.1,"aMS",@progbits,1
        .type   longjmp_msg,@object
@@ -97,6 +96,7 @@ ENTRY (____longjmp_chk)
         mov 1, %g2             /* Delay slot only hit if zero: VAL = 1.  */
 0:
 
+       save    %sp, -96, %sp
        /*
         * Do a "flush register windows trap".  The trap handler in the
         * kernel writes all the register windows to their stack slots, and
@@ -108,14 +108,12 @@ ENTRY (____longjmp_chk)
        ta      ST_FLUSH_WINDOWS
 #ifdef PTR_DEMANGLE
        ld      ENV(g1,JB_PC), %g1 /* Set return PC. */
-       PTR_DEMANGLE2 (%o7, %g1, %g4)
+       PTR_DEMANGLE2 (%i7, %g1, %g4)
 #else
-       ld      ENV(g1,JB_PC), %o7 /* Set return PC. */
+       ld      ENV(g1,JB_PC), %i7 /* Set return PC. */
 #endif
        mov     %g5, %fp
-       sub     %fp, 64, %sp    /* Allocate a register frame. */
-       st      %g3, RW_FP      /* Set saved FP on restore below. */
-       retl
+       jmp     %i7 + 8
         restore %g2, 0, %o0    /* Restore values from above register frame. */
 
 END(____longjmp_chk)