From c0e70b2543f2db96784e2d46595f05869dad24ea Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Mon, 20 Feb 2012 20:50:14 -0800 Subject: [PATCH] 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. --- ChangeLog | 7 +++++++ sysdeps/sparc/sparc32/__longjmp.S | 10 ++++------ .../unix/sysv/linux/sparc/sparc32/____longjmp_chk.S | 10 ++++------ 3 files changed, 15 insertions(+), 12 deletions(-) diff --git a/ChangeLog b/ChangeLog index d0352f62a8..73e51dc758 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,10 @@ +2012-02-20 David S. Miller + + * 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 * 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 7e05c9524b..e4caf7b024 100644 --- a/sysdeps/sparc/sparc32/__longjmp.S +++ b/sysdeps/sparc/sparc32/__longjmp.S @@ -21,7 +21,6 @@ #include #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 dfbf76165a..7246e893a7 100644 --- 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)