adjust base pointer for sysv_amd64.

submit lib

Author: kristjanvalur

lib/sysv_amd64/libstackman.a

@@ -39,31 +39,38 @@ stackman_switch:
 	movq	%rdi, %rax
 	movq	%rsi, %rcx
 #APP
-# 52 "switch_x86_64_gcc.h" 1
+# 56 "switch_x86_64_gcc.h" 1
 	fstcw 10(%rsp)
 	stmxcsr 12(%rsp)
 
 # 0 "" 2
-# 58 "switch_x86_64_gcc.h" 1
-	movq %rsp, %rdx
+# 62 "switch_x86_64_gcc.h" 1
+	movq %rsp, %rbx
 # 0 "" 2
 #NO_APP
+	movq	%rbx, %rdx
 	movl	$0, %esi
-	movq	%rcx, %r14
+	movq	%rcx, %r15
 	movq	%rcx, %rdi
-	movq	%rax, %rbx
+	movq	%rax, %r14
 	call	*%rax
-	movq	%rax, %rdx
 #APP
-# 62 "switch_x86_64_gcc.h" 1
+# 67 "switch_x86_64_gcc.h" 1
 	movq %rax, %rsp
 # 0 "" 2
 #NO_APP
+	subq	%rbx, %rax
+#APP
+# 68 "switch_x86_64_gcc.h" 1
+	addq %rax,  %rbp
+# 0 "" 2
+#NO_APP
+	movq	%rbx, %rdx
 	movl	$1, %esi
-	movq	%r14, %rdi
-	call	*%rbx
+	movq	%r15, %rdi
+	call	*%r14
 #APP
-# 66 "switch_x86_64_gcc.h" 1
+# 72 "switch_x86_64_gcc.h" 1
 	ldmxcsr 12(%rsp)
 	fldcw 10(%rsp)
 
@@ -103,21 +110,21 @@ stackman_call:
 	movq	%rdi, %rax
 	movq	%rsi, %rdi
 #APP
-# 86 "switch_x86_64_gcc.h" 1
+# 92 "switch_x86_64_gcc.h" 1
 	movq %rsp, %rbx
 # 0 "" 2
-# 87 "switch_x86_64_gcc.h" 1
+# 93 "switch_x86_64_gcc.h" 1
 	movq %rsp, %rcx
 # 0 "" 2
-# 90 "switch_x86_64_gcc.h" 1
+# 96 "switch_x86_64_gcc.h" 1
 	movq %rdx, %rsp
 # 0 "" 2
 #NO_APP
 	movq	%rcx, %rdx
 	movl	$2, %esi
 	call	*%rax
 #APP
-# 94 "switch_x86_64_gcc.h" 1
+# 100 "switch_x86_64_gcc.h" 1
 	movq %rbx, %rsp
 # 0 "" 2
 #NO_APP
@@ -129,5 +136,5 @@ stackman_call:
 	.cfi_endproc
 .LFE1:
 	.size	stackman_call, .-stackman_call
-	.ident	"GCC: (Ubuntu 9.3.0-10ubuntu2) 9.3.0"
+	.ident	"GCC: (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0"
 	.section	.note.GNU-stack,"",@progbits

src/platforms/switch_x86_64_gcc.S

@@ -25,6 +25,7 @@
 
 #if !__ASSEMBLER__ && !defined(STACKMAN_ASSEMBLY_SRC)
 /* inline assembly */
+#include <stddef.h>
 #include "../stackman_switch.h"
 
 /* 
@@ -48,7 +49,8 @@ __attribute__((optimize(OPTIMIZE)))
 STACKMAN_LINKAGE_SWITCH_INASM
 void *STACKMAN_SWITCH_INASM_NAME(stackman_cb_t callback, void *context)
 {
-	void *stack_pointer;
+	void *stack_pointer, *stack_pointer2;
+	ptrdiff_t diff;
 	/* assembly to save non-volatile registers, including x87 and mmx */
 	int mxcsr; short x87cw;
 	__asm__ volatile (
@@ -58,10 +60,12 @@ void *STACKMAN_SWITCH_INASM_NAME(stackman_cb_t callback, void *context)
 
 	/* sp = get stack pointer from assembly code */
 	__asm__ ("movq %%rsp, %[result]" : [result] "=r" (stack_pointer));
-	stack_pointer = callback(context, STACKMAN_OP_SAVE, stack_pointer);
+	stack_pointer2 = callback(context, STACKMAN_OP_SAVE, stack_pointer);
+	diff = stack_pointer2 - stack_pointer;
 
 	/* set stack pointer from sp using assembly */
-	__asm__ ("movq %[result], %%rsp" :: [result] "r" (stack_pointer));
+	__asm__ ("movq %[result], %%rsp" :: [result] "r" (stack_pointer2));
+	__asm__ ("addq %[arg],  %%rbp" :: [arg] "r" (diff));
 
 	stack_pointer = callback(context, STACKMAN_OP_RESTORE, stack_pointer);
 	/* restore non-volatile registers from stack */