debug the gc

1 files changed, 22 insertions, 13 deletions

diff --git a/include/gc.s b/include/gc.s
index 636a6a2..ae71d5c 100644
--- a/include/gc.s
+++ b/include/gc.s
@@ -74,6 +74,8 @@ _uskel_alloc:
 	cmp %r14, %rax
 	cmova %rax, %r14
 
+	and $0xfffffffffffffff8, %r14 #align
+
 	alloc_goes_mmap:
 	mov $9, %rax # mmap
 	mov $0, %rdi # addr = NULL
@@ -94,7 +96,7 @@ _uskel_alloc:
 
 _uskel_gc_init:
 	mov %rsi, %r13
-	movq $0x100, _gc_min_alloc
+	movq $0x100, _gc_min_alloc # must be higher than 2x the biggest thunk possible
 	movq $0x180, _gc_grow_ratio
 	movq $0x40, _gc_shrink_ratio
 	mov $0, %rsp # fake original rsp for first alloc run
@@ -121,7 +123,7 @@ _uskel_gc:
 
 	# point the writer to the new memory area
 	mov _write_region_end, %rsp
-	mov %rsp, %rdi # %rdi is "the last scavenged thing"
+	mov %rsp, %r8 # % r8 is the "last thing that was scavenged"
 	
 	# start by evacuating the thunk and cont
 	mov _gc_backup_thunk, %rbp
@@ -139,27 +141,26 @@ _uskel_gc:
 	# scavenge everything
 	_uskel_gc_scavenge:
 	# start at what we wrote last
-	mov %rsp, %rbp
+	mov %rsp, %rbp # rbp is the iterator (conveniently)
+	mov %rsp, %r9 # % r9 stores where we started with this evacuate round
 
 	# if the thing is already scavenged, we didn't write anything, mark done.
-	cmp %rbp, %rdi
+	cmp %rbp, %r8
 	jbe _uskel_gc_scavenge_end
 
 	_uskel_gc_scavenge1:
 	# if all ok, scavenge one thing (moving %rbp) and recheck
-	mov $_uskel_gc_scavenge1_ret, %rsi
 	mov (%rbp), %rax
 	jmp *-020(%rax) # scavenge position in infotable
-	_uskel_gc_scavenge1_ret:
-	cmp %rbp, %rdi
+	_gc_scavenge_ret:
+	cmp %rbp, %r8
 	ja _uskel_gc_scavenge1
 
-	# everything above rsp is now scavenged, continue with next round
-	mov %rsp, %rdi
+	# everything above r9 is now scavenged, continue with next round
+	mov %r9, %r8 # we started at r9, so that is now "done"
 	jmp _uskel_gc_scavenge
 
 	_uskel_gc_scavenge_end:
-
 	# deallocate the old memory region
 	mov $11, %rax # munmap
 	mov _gc_region_end, %rsi
@@ -188,14 +189,22 @@ _uskel_gc:
 _gc_evacuate:
 	# check if we are really out of the target region
 	cmp _write_region_start, %rbp
-	jb _gc_evacuate_ok
+	jb _gc_evacuate_go
 	cmp _write_region_end, %rbp
-	jae _gc_evacuate_ok
+	jae _gc_evacuate_go
+	_gc_evacuate_skip:
 	# if not, let's just jump to cont and leave %rbp as result
 	jmp *%rsi
-	_gc_evacuate_ok:
+	_gc_evacuate_go:
 	# if we should evacuate, jump to the evac routine
+	mov %rbp, %r10
 	mov (%rbp), %rax
 	jmp *-030(%rax)
+	_gc_evacuate_ret:
+	# install the indirection
+	movq $IND_code, 000(%r10)
+	mov %rbp, 010(%r10)
+	jmp *%rsi
+
 
 .endif #_gc_s_file