Make operation sizes great again

mehfooz09 · May 22, 2018 · 3c0c9f8 · 3c0c9f8
1 parent bc0c9d8
commit 3c0c9f8
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Showing 9 changed files with 762 additions and 853 deletions.
diff --git a/emu/decode.h b/emu/decode.h
diff --git a/emu/gadgets-x86/control.S b/emu/gadgets-x86/control.S
@@ -49,5 +49,4 @@
         jmp jit_ret
 .endr
 
-.section .rodata
-.gadget_array_list jmp, COND_LIST
+.gadget_array jmp, COND_LIST
diff --git a/emu/gadgets-x86/gadgets.h b/emu/gadgets-x86/gadgets.h
@@ -2,6 +2,7 @@
 
 # register assignments
 #define _esp r8d
+#define _sp r8w
 #define _ip r9
 #define _eip r9d
 #define _tmp r10d
@@ -21,9 +22,6 @@
     jmp *-8(%_ip)
 .endm
 
-# using a gas macro for this works fine on gcc but not on clang
-#define REG_LIST eax,ecx,edx,ebx,esp,ebp,esi,edi
-
 # memory reading and writing
 # TODO cross-page access handling (but it's going to be so slow :cry:)
 .irp type, read,write
@@ -48,36 +46,32 @@
 
 .endr
 
-# a gadget for each register
-.macro .reg_gadgets type
-    .irp reg, REG_LIST
-        .gadget \type\()_\reg
-        .ifnc \reg,esp
-            x \reg
-        .else
-            x _esp
-        .endif
-        gret
-    .endr
-    .purgem x
-.endm
+# sync with enum reg
+#define REG_LIST reg_a,reg_c,reg_d,reg_b,reg_sp,reg_bp,reg_si,reg_di
+# sync with enum arg
+#define GADGET_LIST REG_LIST,imm,mem,addr
 
 # an array of gadgets
-.macro .gadget_array_list type, list:vararg
-    .global \type\()_gadgets
-    .type \type\()_gadgets,@object
-    \type\()_gadgets:
-        .irp arg, \list 
-            .ifndef gadget_\type\()_\arg
-                .set gadget_\type\()_\arg, 0
-            .endif
-            .quad gadget_\type\()_\arg
-        .endr
+.macro .gadget_array type, list:vararg
+    .pushsection .rodata
+    .gadget_array_start \type
+        gadgets \type, \list
+    .popsection
 .endm
 
-.macro .gadget_array type
-    # This should stay in sync with enum arg in emu/gen.c
-    .gadget_array_list \type, eax,ecx,edx,ebx,esp,ebp,esi,edi,ax,cx,dx,bx,sp,bp,si,di,imm,mem32,mem8,addr
+.macro .gadget_array_start name
+    .global \name\()_gadgets
+    .type \name\()_gadgets,@object
+    \name\()_gadgets:
+.endm
+
+.macro gadgets type, list:vararg
+    .irp arg, \list
+        .ifndef gadget_\type\()_\arg
+            .set gadget_\type\()_\arg, 0
+        .endif
+        .quad gadget_\type\()_\arg
+    .endr
 .endm
 
 .macro save_c

diff --git a/emu/gadgets-x86/math.S b/emu/gadgets-x86/math.S
@@ -1,7 +1,7 @@
 #include "gadgets.h"
 # asmsyntax=gas (for vim)
 
-.gadget load_addr
+.gadget load32_addr
     movl %_addr, %_tmp
     gret
 
@@ -18,16 +18,16 @@
     andl $~AF_FLAG, CPU_eflags(%_cpu)
     andl $~AF_OPS, CPU_flags_res(%_cpu)
 .endm
-.macro setf_zsp res
-    mov \res, CPU_res(%_cpu)
+.macro setf_zsp res, ss
+    .ifnc ss,l
+        movl $0, CPU_res(%_cpu)
+    .endif
+    mov\ss \res, CPU_res(%_cpu)
     orl $(ZF_RES|SF_RES|PF_RES), CPU_flags_res(%_cpu)
 .endm
 
 # cool thing where I just write a few nested loops and it generates all the gadgets automatically
 
-# bwl
-# bwd
-
 #define ifin(thing, ...) irp da_op, __VA_ARGS__; .ifc thing,\da_op
 #define endifin endif; .endr
 #undef _tmp
@@ -49,54 +49,105 @@
         .ifin(\op, add,sub)
             setf_oc
         .endifin
-        setf_zsp %_tmp\s
+        setf_zsp %_tmp\s, \ss
     .endif; .endif
 .endm
-.macro do_op op, arg, size
+.macro do_op op, size, arg
     .ifc \size,8
         _do_op \op, \arg, \size, b, b
+    .else; .ifc \size,16
+        _do_op \op, \arg, \size, w, w
     .else; .ifc \size,32
         _do_op \op, \arg, \size, d, l
     .else
         .error "bad size"
-    .endif; .endif
+    .endif; .endif; .endif
 .endm
 #undef _tmp
 #define _tmp r10d
 
-.irp op, load,store,add,and,sub,xor
-    .macro x reg
-        do_op \op, %\reg, 32
-    .endm
-    .reg_gadgets \op
+.macro do_reg_op op, size, reg
+    .gadget \op\size\()_reg_\reg
+        .if \size == 32
+            do_op \op, \size, %e\reg\()x
+        .elseif \size == 16
+            do_op \op, \size, %\reg\()x
+        .elseif \size == 8
+            do_op \op, \size, %\reg\()l
+        .endif
+        gret
+.endm
+
+.macro do_hi_op op, size, reg
+    xchg %\reg\()h, %\reg\()l
+    do_op \op, \size, %\reg\()l
+    xchg %\reg\()h, %\reg\()l
+.endm
 
+.macro do_op_size op, size
     .ifnc \op,store
-        .gadget \op\()_imm
-            do_op \op, (%_ip), 32
+        .gadget \op\size\()_imm
+            do_op \op, \size, (%_ip)
             gret 1
     .endif
 
-    .irp size, 8,32
-        .gadget \op\()_mem\size
-            .ifc \op,store
-                write_prep
-            .else
-                read_prep
+    .gadget \op\size\()_mem
+        .ifc \op,store
+            write_prep
+        .else
+            read_prep
+        .endif
+        do_op \op, \size, (%_addrq)
+        gret
+
+    .irp reg, a,b,c,d
+        do_reg_op \op, \size, \reg
+    .endr
+
+    .irp reg, si,di,sp,bp
+        .gadget \op\size\()_reg_\reg
+            .if \size == 32
+                .ifnc \reg,sp
+                    do_op \op, \size, %e\reg
+                .else
+                    do_op \op, \size, %_esp
+                .endif
+            .elseif \size == 16
+                .ifnc \reg,sp
+                    do_op \op, \size, %\reg
+                .else
+                    do_op \op, \size, %_sp
+                .endif
+            .elseif \size == 8
+                .ifc \reg,sp; do_hi_op \op, \size, a; .else
+                .ifc \reg,bp; do_hi_op \op, \size, c; .else
+                .ifc \reg,si; do_hi_op \op, \size, d; .else
+                .ifc \reg,di; do_hi_op \op, \size, b
+                .endif; .endif; .endif; .endif
             .endif
-            do_op \op, (%_addrq), \size
             gret
     .endr
+.endm
+
+.irp op, load,store,add,and,sub,xor
+    .irp size, 8,16,32
+        do_op_size \op, \size
+    .endr
 
-    .section .rodata
-    .gadget_array \op
-    .previous
+    .pushsection .rodata
+    .gadget_array_start \op
+        # sync with enum size
+        .irp size, 8,16,32
+            gadgets \op\size, GADGET_LIST
+        .endr
+    .popsection
 .endr
 
 .irp op, inc,dec
     .gadget \op
         setf_a src=$1 dst=%_tmp, ss=l
         \op\()l %_tmp
         seto CPU_of(%_cpu)
-        setf_zsp %_tmp
+        setf_zsp %_tmp, l
         gret
 .endr
diff --git a/emu/gadgets-x86/memory.S b/emu/gadgets-x86/memory.S
@@ -14,24 +14,43 @@
     add $4, %_esp
     gret
 
-.macro x reg
-    movl %\reg, %_addr
-    addl (%_ip), %_addr
-    gret 1
+.macro _invoke macro, reg, post
+    \macro reg_\reg, e\reg\post
+.endm
+.macro .each_reg macro
+    .irp reg, a,b,c,d
+        _invoke \macro, \reg, x
+    .endr
+    .irp reg, si,di,bp
+        _invoke \macro, \reg,
+    .endr
+    \macro reg_sp, _esp
 .endm
-.reg_gadgets addr
 
-.irp reg, REG_LIST
+.macro x name, reg
+    .gadget addr_\name
+        movl %\reg, %_addr
+        addl (%_ip), %_addr
+        gret 1
+.endm
+.each_reg x
+.purgem x
+.gadget_array addr, REG_LIST
+
+.macro x name, reg
     .irp times, 1,2,4
-        .gadget si_\reg\()_\times
+        .gadget si_\name\()_\times
             .ifnc \reg,esp
                 leal (%_addr,%\reg,\times), %_addr
             .else
                 leal (%_addr,%_esp,\times), %_addr
             .endif
             gret
     .endr
-.endr
+.endm
+.each_reg x
+.purgem x
+
 .section .rodata
 .global si_gadgets
 si_gadgets:
@@ -68,5 +87,4 @@ segfault:
     movl $INT_GPF, %_tmp
     jmp jit_exit
 
-.section .rodata
-.gadget_array_list addr, REG_LIST
+.gadget_array, REG_LIST