aboutsummaryrefslogtreecommitdiffstats
path: root/main/gcc/0001-i386-Move-struct-ix86_frame-to-machine_function.patch
blob: ecec2bad66e6ab62b67d9b6a3dbe1c6361ebd4d2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
From b1d2df5090abc9202a7bf2d224ac90de22908d21 Mon Sep 17 00:00:00 2001
From: hjl <hjl@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Mon, 15 Jan 2018 11:27:24 +0000
Subject: [PATCH 01/13] i386: Move struct ix86_frame to machine_function

Make ix86_frame available to i386 code generation.  This is needed to
backport the patch set of -mindirect-branch= to mitigate variant #2 of
the speculative execution vulnerabilities on x86 processors identified
by CVE-2017-5715, aka Spectre.

	Backport from mainline
	2017-06-01  Bernd Edlinger  <bernd.edlinger@hotmail.de>

	* config/i386/i386.c (ix86_frame): Moved to ...
	* config/i386/i386.h (ix86_frame): Here.
	(machine_function): Add frame.
	* config/i386/i386.c (ix86_compute_frame_layout): Repace the
	frame argument with &cfun->machine->frame.
	(ix86_can_use_return_insn_p): Don't pass &frame to
	ix86_compute_frame_layout.  Copy frame from cfun->machine->frame.
	(ix86_can_eliminate): Likewise.
	(ix86_expand_prologue): Likewise.
	(ix86_expand_epilogue): Likewise.
	(ix86_expand_split_stack_prologue): Likewise.
---
 gcc/config/i386/i386.c | 68 ++++++++++----------------------------------------
 gcc/config/i386/i386.h | 53 ++++++++++++++++++++++++++++++++++++++-
 2 files changed, 65 insertions(+), 56 deletions(-)

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 8b5faac5129..a1ff32b648b 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -2434,53 +2434,6 @@ struct GTY(()) stack_local_entry {
   struct stack_local_entry *next;
 };
 
-/* Structure describing stack frame layout.
-   Stack grows downward:
-
-   [arguments]
-					<- ARG_POINTER
-   saved pc
-
-   saved static chain			if ix86_static_chain_on_stack
-
-   saved frame pointer			if frame_pointer_needed
-					<- HARD_FRAME_POINTER
-   [saved regs]
-					<- regs_save_offset
-   [padding0]
-
-   [saved SSE regs]
-					<- sse_regs_save_offset
-   [padding1]          |
-		       |		<- FRAME_POINTER
-   [va_arg registers]  |
-		       |
-   [frame]	       |
-		       |
-   [padding2]	       | = to_allocate
-					<- STACK_POINTER
-  */
-struct ix86_frame
-{
-  int nsseregs;
-  int nregs;
-  int va_arg_size;
-  int red_zone_size;
-  int outgoing_arguments_size;
-
-  /* The offsets relative to ARG_POINTER.  */
-  HOST_WIDE_INT frame_pointer_offset;
-  HOST_WIDE_INT hard_frame_pointer_offset;
-  HOST_WIDE_INT stack_pointer_offset;
-  HOST_WIDE_INT hfp_save_offset;
-  HOST_WIDE_INT reg_save_offset;
-  HOST_WIDE_INT sse_reg_save_offset;
-
-  /* When save_regs_using_mov is set, emit prologue using
-     move instead of push instructions.  */
-  bool save_regs_using_mov;
-};
-
 /* Which cpu are we scheduling for.  */
 enum attr_cpu ix86_schedule;
 
@@ -2572,7 +2525,7 @@ static unsigned int ix86_function_arg_boundary (machine_mode,
 						const_tree);
 static rtx ix86_static_chain (const_tree, bool);
 static int ix86_function_regparm (const_tree, const_tree);
-static void ix86_compute_frame_layout (struct ix86_frame *);
+static void ix86_compute_frame_layout (void);
 static bool ix86_expand_vector_init_one_nonzero (bool, machine_mode,
 						 rtx, rtx, int);
 static void ix86_add_new_builtins (HOST_WIDE_INT);
@@ -10944,7 +10897,8 @@ ix86_can_use_return_insn_p (void)
   if (crtl->args.pops_args && crtl->args.size >= 32768)
     return 0;
 
-  ix86_compute_frame_layout (&frame);
+  ix86_compute_frame_layout ();
+  frame = cfun->machine->frame;
   return (frame.stack_pointer_offset == UNITS_PER_WORD
 	  && (frame.nregs + frame.nsseregs) == 0);
 }
@@ -11355,8 +11309,8 @@ ix86_can_eliminate (const int from, const int to)
 HOST_WIDE_INT
 ix86_initial_elimination_offset (int from, int to)
 {
-  struct ix86_frame frame;
-  ix86_compute_frame_layout (&frame);
+  ix86_compute_frame_layout ();
+  struct ix86_frame frame = cfun->machine->frame;
 
   if (from == ARG_POINTER_REGNUM && to == HARD_FRAME_POINTER_REGNUM)
     return frame.hard_frame_pointer_offset;
@@ -11395,8 +11349,9 @@ ix86_builtin_setjmp_frame_value (void)
 /* Fill structure ix86_frame about frame of currently computed function.  */
 
 static void
-ix86_compute_frame_layout (struct ix86_frame *frame)
+ix86_compute_frame_layout (void)
 {
+  struct ix86_frame *frame = &cfun->machine->frame;
   unsigned HOST_WIDE_INT stack_alignment_needed;
   HOST_WIDE_INT offset;
   unsigned HOST_WIDE_INT preferred_alignment;
@@ -12702,7 +12657,8 @@ ix86_expand_prologue (void)
   m->fs.sp_offset = INCOMING_FRAME_SP_OFFSET;
   m->fs.sp_valid = true;
 
-  ix86_compute_frame_layout (&frame);
+  ix86_compute_frame_layout ();
+  frame = m->frame;
 
   if (!TARGET_64BIT && ix86_function_ms_hook_prologue (current_function_decl))
     {
@@ -13379,7 +13335,8 @@ ix86_expand_epilogue (int style)
   bool using_drap;
 
   ix86_finalize_stack_realign_flags ();
-  ix86_compute_frame_layout (&frame);
+  ix86_compute_frame_layout ();
+  frame = m->frame;
 
   m->fs.sp_valid = (!frame_pointer_needed
 		    || (crtl->sp_is_unchanging
@@ -13876,7 +13833,8 @@ ix86_expand_split_stack_prologue (void)
   gcc_assert (flag_split_stack && reload_completed);
 
   ix86_finalize_stack_realign_flags ();
-  ix86_compute_frame_layout (&frame);
+  ix86_compute_frame_layout ();
+  frame = cfun->machine->frame;
   allocate = frame.stack_pointer_offset - INCOMING_FRAME_SP_OFFSET;
 
   /* This is the label we will branch to if we have enough stack
diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
index 8113f83c7fd..54144166172 100644
--- a/gcc/config/i386/i386.h
+++ b/gcc/config/i386/i386.h
@@ -2427,9 +2427,56 @@ enum avx_u128_state
 
 #define FASTCALL_PREFIX '@'
 
+#ifndef USED_FOR_TARGET
+/* Structure describing stack frame layout.
+   Stack grows downward:
+
+   [arguments]
+					<- ARG_POINTER
+   saved pc
+
+   saved static chain			if ix86_static_chain_on_stack
+
+   saved frame pointer			if frame_pointer_needed
+					<- HARD_FRAME_POINTER
+   [saved regs]
+					<- regs_save_offset
+   [padding0]
+
+   [saved SSE regs]
+					<- sse_regs_save_offset
+   [padding1]          |
+		       |		<- FRAME_POINTER
+   [va_arg registers]  |
+		       |
+   [frame]	       |
+		       |
+   [padding2]	       | = to_allocate
+					<- STACK_POINTER
+  */
+struct GTY(()) ix86_frame
+{
+  int nsseregs;
+  int nregs;
+  int va_arg_size;
+  int red_zone_size;
+  int outgoing_arguments_size;
+
+  /* The offsets relative to ARG_POINTER.  */
+  HOST_WIDE_INT frame_pointer_offset;
+  HOST_WIDE_INT hard_frame_pointer_offset;
+  HOST_WIDE_INT stack_pointer_offset;
+  HOST_WIDE_INT hfp_save_offset;
+  HOST_WIDE_INT reg_save_offset;
+  HOST_WIDE_INT sse_reg_save_offset;
+
+  /* When save_regs_using_mov is set, emit prologue using
+     move instead of push instructions.  */
+  bool save_regs_using_mov;
+};
+
 /* Machine specific frame tracking during prologue/epilogue generation.  */
 
-#ifndef USED_FOR_TARGET
 struct GTY(()) machine_frame_state
 {
   /* This pair tracks the currently active CFA as reg+offset.  When reg
@@ -2475,6 +2522,9 @@ struct GTY(()) machine_function {
   int varargs_fpr_size;
   int optimize_mode_switching[MAX_386_ENTITIES];
 
+  /* Cached initial frame layout for the current function.  */
+  struct ix86_frame frame;
+
   /* Number of saved registers USE_FAST_PROLOGUE_EPILOGUE
      has been computed for.  */
   int use_fast_prologue_epilogue_nregs;
@@ -2554,6 +2604,7 @@ struct GTY(()) machine_function {
 #define ix86_current_function_calls_tls_descriptor \
   (ix86_tls_descriptor_calls_expanded_in_cfun && df_regs_ever_live_p (SP_REG))
 #define ix86_static_chain_on_stack (cfun->machine->static_chain_on_stack)
+#define ix86_red_zone_size (cfun->machine->frame.red_zone_size)
 
 /* Control behavior of x86_file_start.  */
 #define X86_FILE_START_VERSION_DIRECTIVE false
-- 
2.16.3