File gcc7-aarch64-bsc1214052.patch of Package cross-aarch64-gcc7

Overview Repositories Revisions Requests Users Attributes Meta

File gcc7-aarch64-bsc1214052.patch of Package cross-aarch64-gcc7 (Revision 222157e82135407d7ae8f1ddc13876bc)

Currently displaying revision 222157e82135407d7ae8f1ddc13876bc , Show latest

From 04553281f42e5c4340d554a93d1a73006365d8fb Mon Sep 17 00:00:00 2001
From: Richard Sandiford <richard.sandiford@arm.com>
Date: Fri, 16 Jun 2023 17:00:51 +0100
Subject: [PATCH 1/7] aarch64: Explicitly handle frames with no saved registers
To: gcc-patches@gcc.gnu.org

If a frame has no saved registers, it can be allocated in one go.
There is no need to treat the areas below and above the saved
registers as separate.

This is a no-op as thing stand, since a leaf function will have
no outgoing arguments, and so all the frame will be above where
the saved registers normally go.

gcc/
	* config/aarch64/aarch64.c (aarch64_layout_frame): Explicitly
	allocate the frame in one go if there are no saved registers.
---
 gcc/config/aarch64/aarch64.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 4e94be3b0b4..bb4f6020e5d 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -2901,8 +2901,10 @@ aarch64_layout_frame (void)
   else if (cfun->machine->frame.wb_candidate1 != INVALID_REGNUM)
     max_push_offset = 256;
 
-  if (cfun->machine->frame.frame_size < max_push_offset
-      && crtl->outgoing_args_size == 0)
+  if (cfun->machine->frame.saved_regs_size == 0)
+    cfun->machine->frame.initial_adjust = cfun->machine->frame.frame_size;
+  else if (cfun->machine->frame.frame_size < max_push_offset
+	   && crtl->outgoing_args_size == 0)
     {
       /* Simple, small frame with no outgoing arguments:
 	 stp reg1, reg2, [sp, -frame_size]!
-- 
2.25.1

From e97c93de7ceadad75774f897424a50ece3215129 Mon Sep 17 00:00:00 2001
From: Richard Sandiford <richard.sandiford@arm.com>
Date: Fri, 16 Jun 2023 16:55:12 +0100
Subject: [PATCH 2/7] aarch64: Add bytes_below_hard_fp to frame info
To: gcc-patches@gcc.gnu.org

The frame layout code currently hard-codes the assumption that
the number of bytes below the saved registers is equal to the
size of the outgoing arguments.  This patch abstracts that
value into a new field of aarch64_frame.

gcc/
	* config/aarch64/aarch64.h (aarch64_frame::bytes_below_hard_fp): New
	field.
	* config/aarch64/aarch64.c (aarch64_layout_frame): Initialize it,
	and use it instead of crtl->outgoing_args_size.
	(aarch64_get_separate_components): Use bytes_below_hard_fp instead
	of outgoing_args_size.
	(aarch64_process_components): Likewise.
---
 gcc/config/aarch64/aarch64.c | 40 +++++++++++++++++++++---------------
 gcc/config/aarch64/aarch64.h |  6 +++++-
 2 files changed, 28 insertions(+), 18 deletions(-)

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index bb4f6020e5d..12df8bb783c 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -2826,6 +2826,8 @@ aarch64_layout_frame (void)
 	last_fp_reg = regno;
       }
 
+  cfun->machine->frame.bytes_below_hard_fp = crtl->outgoing_args_size;
+
   if (frame_pointer_needed)
     {
       /* FP and LR are placed in the linkage record.  */
@@ -2885,7 +2887,7 @@ aarch64_layout_frame (void)
 
   cfun->machine->frame.frame_size
     = ROUND_UP (cfun->machine->frame.hard_fp_offset
-		+ crtl->outgoing_args_size,
+		+ cfun->machine->frame.bytes_below_hard_fp,
 		STACK_BOUNDARY / BITS_PER_UNIT);
 
   cfun->machine->frame.locals_offset = cfun->machine->frame.saved_varargs_size;
@@ -2904,32 +2906,33 @@ aarch64_layout_frame (void)
   if (cfun->machine->frame.saved_regs_size == 0)
     cfun->machine->frame.initial_adjust = cfun->machine->frame.frame_size;
   else if (cfun->machine->frame.frame_size < max_push_offset
-	   && crtl->outgoing_args_size == 0)
+	   && cfun->machine->frame.bytes_below_hard_fp == 0)
     {
-      /* Simple, small frame with no outgoing arguments:
+      /* Simple, small frame with no data below the saved registers.
 	 stp reg1, reg2, [sp, -frame_size]!
 	 stp reg3, reg4, [sp, 16]  */
       cfun->machine->frame.callee_adjust = cfun->machine->frame.frame_size;
     }
-  else if ((crtl->outgoing_args_size
+  else if ((cfun->machine->frame.bytes_below_hard_fp
 	    + cfun->machine->frame.saved_regs_size < 512)
 	   && !(cfun->calls_alloca
 		&& cfun->machine->frame.hard_fp_offset < max_push_offset))
     {
-      /* Frame with small outgoing arguments:
+      /* Frame with small area below the saved registers:
 	 sub sp, sp, frame_size
-	 stp reg1, reg2, [sp, outgoing_args_size]
-	 stp reg3, reg4, [sp, outgoing_args_size + 16]  */
+	 stp reg1, reg2, [sp, bytes_below_hard_fp]
+	 stp reg3, reg4, [sp, bytes_below_hard_fp + 16]  */
       cfun->machine->frame.initial_adjust = cfun->machine->frame.frame_size;
       cfun->machine->frame.callee_offset
 	= cfun->machine->frame.frame_size - cfun->machine->frame.hard_fp_offset;
     }
   else if (cfun->machine->frame.hard_fp_offset < max_push_offset)
     {
-      /* Frame with large outgoing arguments but a small local area:
+      /* Frame with large area below the saved registers, but with a
+	 small area above:
 	 stp reg1, reg2, [sp, -hard_fp_offset]!
 	 stp reg3, reg4, [sp, 16]
-	 sub sp, sp, outgoing_args_size  */
+	 sub sp, sp, bytes_below_hard_fp  */
       cfun->machine->frame.callee_adjust = cfun->machine->frame.hard_fp_offset;
       cfun->machine->frame.final_adjust
 	= cfun->machine->frame.frame_size - cfun->machine->frame.callee_adjust;
@@ -2945,17 +2948,19 @@ aarch64_layout_frame (void)
       cfun->machine->frame.callee_adjust = varargs_and_saved_regs_size;
       cfun->machine->frame.final_adjust
 	= cfun->machine->frame.frame_size - cfun->machine->frame.callee_adjust;
+      cfun->machine->frame.bytes_below_hard_fp
+	= cfun->machine->frame.final_adjust;
       cfun->machine->frame.hard_fp_offset = cfun->machine->frame.callee_adjust;
       cfun->machine->frame.locals_offset = cfun->machine->frame.hard_fp_offset;
     }
   else
     {
-      /* Frame with large local area and outgoing arguments using frame pointer:
+      /* General case:
 	 sub sp, sp, hard_fp_offset
 	 stp x29, x30, [sp, 0]
 	 add x29, sp, 0
 	 stp reg3, reg4, [sp, 16]
-	 sub sp, sp, outgoing_args_size  */
+	 sub sp, sp, bytes_below_hard_fp  */
       cfun->machine->frame.initial_adjust = cfun->machine->frame.hard_fp_offset;
       cfun->machine->frame.final_adjust
 	= cfun->machine->frame.frame_size - cfun->machine->frame.initial_adjust;
@@ -3313,9 +3318,11 @@ aarch64_get_separate_components (void)
     if (aarch64_register_saved_on_entry (regno))
       {
 	HOST_WIDE_INT offset = cfun->machine->frame.reg_offset[regno];
+
+	/* Get the offset relative to the register we'll use.  */
 	if (!frame_pointer_needed)
-	  offset += cfun->machine->frame.frame_size
-		    - cfun->machine->frame.hard_fp_offset;
+	  offset += cfun->machine->frame.bytes_below_hard_fp;
+
 	/* Check that we can access the stack slot of the register with one
 	   direct load with no adjustments needed.  */
 	if (offset_12bit_unsigned_scaled_p (DImode, offset))
@@ -3418,8 +3425,8 @@ aarch64_process_components (sbitmap components, bool prologue_p)
       rtx reg = gen_rtx_REG (mode, regno);
       HOST_WIDE_INT offset = cfun->machine->frame.reg_offset[regno];
       if (!frame_pointer_needed)
-	offset += cfun->machine->frame.frame_size
-		  - cfun->machine->frame.hard_fp_offset;
+	offset += cfun->machine->frame.bytes_below_hard_fp;
+
       rtx addr = plus_constant (Pmode, ptr_reg, offset);
       rtx mem = gen_frame_mem (mode, addr);
 
@@ -3460,8 +3467,7 @@ aarch64_process_components (sbitmap components, bool prologue_p)
       /* REGNO2 can be saved/restored in a pair with REGNO.  */
       rtx reg2 = gen_rtx_REG (mode, regno2);
       if (!frame_pointer_needed)
-	offset2 += cfun->machine->frame.frame_size
-		  - cfun->machine->frame.hard_fp_offset;
+	offset2 += cfun->machine->frame.bytes_below_hard_fp;
       rtx addr2 = plus_constant (Pmode, ptr_reg, offset2);
       rtx mem2 = gen_frame_mem (mode, addr2);
       rtx set2 = prologue_p ? gen_rtx_SET (mem2, reg2)
diff --git a/gcc/config/aarch64/aarch64.h b/gcc/config/aarch64/aarch64.h
index ddf833ebfe8..6dc6ef2b989 100644
--- a/gcc/config/aarch64/aarch64.h
+++ b/gcc/config/aarch64/aarch64.h
@@ -558,9 +558,13 @@ struct GTY (()) aarch64_frame
   HOST_WIDE_INT saved_varargs_size;
 
   /* The size of the saved callee-save int/FP registers.  */
-
   HOST_WIDE_INT saved_regs_size;
 
+  /* The number of bytes between the bottom of the static frame (the bottom
+     of the outgoing arguments) and the hard frame pointer.  This value is
+     always a multiple of STACK_BOUNDARY.  */
+  HOST_WIDE_INT bytes_below_hard_fp;
+
   /* Offset from the base of the frame (incomming SP) to the
      top of the locals area.  This value is always a multiple of
      STACK_BOUNDARY.  */
-- 
2.25.1

From e628f34ef3a7db3a75aa146b3e75099a9c431d20 Mon Sep 17 00:00:00 2001
From: Richard Sandiford <richard.sandiford@arm.com>
Date: Tue, 27 Jun 2023 11:25:40 +0100
Subject: [PATCH 3/7] aarch64: Rename locals_offset to bytes_above_locals
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
To: gcc-patches@gcc.gnu.org

locals_offset was described as:

/* Offset from the base of the frame (incomming SP) to the
     top of the locals area.  This value is always a multiple of
     STACK_BOUNDARY.  */

This is implicitly an “upside down” view of the frame: the incoming
SP is at offset 0, and anything N bytes below the incoming SP is at
offset N (rather than -N).

However, reg_offset instead uses a “right way up” view; that is,
it views offsets in address terms.  Something above X is at a
positive offset from X and something below X is at a negative
offset from X.

Also, even on FRAME_GROWS_DOWNWARD targets like AArch64,
target-independent code views offsets in address terms too:
locals are allocated at negative offsets to virtual_stack_vars.

It seems confusing to have *_offset fields of the same structure
using different polarities like this.  This patch tries to avoid
that by renaming locals_offset to bytes_above_locals.

gcc/
	* config/aarch64/aarch64.h (aarch64_frame::locals_offset): Rename to...
	(aarch64_frame::bytes_above_locals): ...this.
	* config/aarch64/aarch64.c (aarch64_layout_frame)
	(aarch64_initial_elimination_offset): Update accordingly.
---
 gcc/config/aarch64/aarch64.c | 12 +++++++-----
 gcc/config/aarch64/aarch64.h |  6 +++---
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 12df8bb783c..27dd3b7a62b 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -2890,7 +2890,8 @@ aarch64_layout_frame (void)
 		+ cfun->machine->frame.bytes_below_hard_fp,
 		STACK_BOUNDARY / BITS_PER_UNIT);
 
-  cfun->machine->frame.locals_offset = cfun->machine->frame.saved_varargs_size;
+  cfun->machine->frame.bytes_above_locals
+    = cfun->machine->frame.saved_varargs_size;
 
   cfun->machine->frame.initial_adjust = 0;
   cfun->machine->frame.final_adjust = 0;
@@ -2951,7 +2952,8 @@ aarch64_layout_frame (void)
       cfun->machine->frame.bytes_below_hard_fp
 	= cfun->machine->frame.final_adjust;
       cfun->machine->frame.hard_fp_offset = cfun->machine->frame.callee_adjust;
-      cfun->machine->frame.locals_offset = cfun->machine->frame.hard_fp_offset;
+      cfun->machine->frame.bytes_above_locals
+	= cfun->machine->frame.hard_fp_offset;
     }
   else
     {
@@ -5653,14 +5655,14 @@ aarch64_initial_elimination_offset (unsigned from, unsigned to)
 
       if (from == FRAME_POINTER_REGNUM)
 	return cfun->machine->frame.hard_fp_offset
-	       - cfun->machine->frame.locals_offset;
+	       - cfun->machine->frame.bytes_above_locals;
     }
 
   if (to == STACK_POINTER_REGNUM)
     {
       if (from == FRAME_POINTER_REGNUM)
-	  return cfun->machine->frame.frame_size
-		 - cfun->machine->frame.locals_offset;
+	return cfun->machine->frame.frame_size
+	       - cfun->machine->frame.bytes_above_locals;
     }
 
   return cfun->machine->frame.frame_size;
diff --git a/gcc/config/aarch64/aarch64.h b/gcc/config/aarch64/aarch64.h
index 6dc6ef2b989..79af237ada6 100644
--- a/gcc/config/aarch64/aarch64.h
+++ b/gcc/config/aarch64/aarch64.h
@@ -565,10 +565,10 @@ struct GTY (()) aarch64_frame
      always a multiple of STACK_BOUNDARY.  */
   HOST_WIDE_INT bytes_below_hard_fp;
 
-  /* Offset from the base of the frame (incomming SP) to the
-     top of the locals area.  This value is always a multiple of
+  /* The number of bytes between the top of the locals area and the top
+     of the frame (the incomming SP).  This value is always a multiple of
      STACK_BOUNDARY.  */
-  HOST_WIDE_INT locals_offset;
+  HOST_WIDE_INT bytes_above_locals;
 
   /* Offset from the base of the frame (incomming SP) to the
      hard_frame_pointer.  This value is always a multiple of
-- 
2.25.1

From da0132a4cd2eb26ecaff20578bf2753b20014223 Mon Sep 17 00:00:00 2001
From: Richard Sandiford <richard.sandiford@arm.com>
Date: Tue, 27 Jun 2023 11:28:11 +0100
Subject: [PATCH 4/7] aarch64: Rename hard_fp_offset to bytes_above_hard_fp
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
To: gcc-patches@gcc.gnu.org

Similarly to the previous locals_offset patch, hard_fp_offset
was described as:

/* Offset from the base of the frame (incomming SP) to the
     hard_frame_pointer.  This value is always a multiple of
     STACK_BOUNDARY.  */
  poly_int64 hard_fp_offset;

which again took an “upside-down” view: higher offsets meant lower
addresses.  This patch renames the field to bytes_above_hard_fp instead.

gcc/
	* config/aarch64/aarch64.h (aarch64_frame::hard_fp_offset): Rename
	to...
	(aarch64_frame::bytes_above_hard_fp): ...this.
	* config/aarch64/aarch64.c (aarch64_layout_frame)
	(aarch64_expand_prologue): Update accordingly.
	(aarch64_initial_elimination_offset): Likewise.
---
 gcc/config/aarch64/aarch64.c | 29 ++++++++++++++++-------------
 gcc/config/aarch64/aarch64.h |  6 +++---
 2 files changed, 19 insertions(+), 16 deletions(-)

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 27dd3b7a62b..e3c36abb1e3 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -2881,12 +2881,12 @@ aarch64_layout_frame (void)
   HOST_WIDE_INT varargs_and_saved_regs_size
     = offset + cfun->machine->frame.saved_varargs_size;
 
-  cfun->machine->frame.hard_fp_offset
+  cfun->machine->frame.bytes_above_hard_fp
     = ROUND_UP (varargs_and_saved_regs_size + get_frame_size (),
 		STACK_BOUNDARY / BITS_PER_UNIT);
 
   cfun->machine->frame.frame_size
-    = ROUND_UP (cfun->machine->frame.hard_fp_offset
+    = ROUND_UP (cfun->machine->frame.bytes_above_hard_fp
 		+ cfun->machine->frame.bytes_below_hard_fp,
 		STACK_BOUNDARY / BITS_PER_UNIT);
 
@@ -2917,7 +2917,7 @@ aarch64_layout_frame (void)
   else if ((cfun->machine->frame.bytes_below_hard_fp
 	    + cfun->machine->frame.saved_regs_size < 512)
 	   && !(cfun->calls_alloca
-		&& cfun->machine->frame.hard_fp_offset < max_push_offset))
+		&& cfun->machine->frame.bytes_above_hard_fp < max_push_offset))
     {
       /* Frame with small area below the saved registers:
 	 sub sp, sp, frame_size
@@ -2925,16 +2925,17 @@ aarch64_layout_frame (void)
 	 stp reg3, reg4, [sp, bytes_below_hard_fp + 16]  */
       cfun->machine->frame.initial_adjust = cfun->machine->frame.frame_size;
       cfun->machine->frame.callee_offset
-	= cfun->machine->frame.frame_size - cfun->machine->frame.hard_fp_offset;
+	= cfun->machine->frame.frame_size - cfun->machine->frame.bytes_above_hard_fp;
     }
-  else if (cfun->machine->frame.hard_fp_offset < max_push_offset)
+  else if (cfun->machine->frame.bytes_above_hard_fp < max_push_offset)
     {
       /* Frame with large area below the saved registers, but with a
 	 small area above:
-	 stp reg1, reg2, [sp, -hard_fp_offset]!
+	 stp reg1, reg2, [sp, -bytes_above_hard_fp]!
 	 stp reg3, reg4, [sp, 16]
 	 sub sp, sp, bytes_below_hard_fp  */
-      cfun->machine->frame.callee_adjust = cfun->machine->frame.hard_fp_offset;
+      cfun->machine->frame.callee_adjust
+	= cfun->machine->frame.bytes_above_hard_fp;
       cfun->machine->frame.final_adjust
 	= cfun->machine->frame.frame_size - cfun->machine->frame.callee_adjust;
     }
@@ -2951,19 +2952,21 @@ aarch64_layout_frame (void)
 	= cfun->machine->frame.frame_size - cfun->machine->frame.callee_adjust;
       cfun->machine->frame.bytes_below_hard_fp
 	= cfun->machine->frame.final_adjust;
-      cfun->machine->frame.hard_fp_offset = cfun->machine->frame.callee_adjust;
+      cfun->machine->frame.bytes_above_hard_fp
+	= cfun->machine->frame.callee_adjust;
       cfun->machine->frame.bytes_above_locals
-	= cfun->machine->frame.hard_fp_offset;
+	= cfun->machine->frame.bytes_above_hard_fp;
     }
   else
     {
       /* General case:
-	 sub sp, sp, hard_fp_offset
+	 sub sp, sp, bytes_above_hard_fp
 	 stp x29, x30, [sp, 0]
 	 add x29, sp, 0
 	 stp reg3, reg4, [sp, 16]
 	 sub sp, sp, bytes_below_hard_fp  */
-      cfun->machine->frame.initial_adjust = cfun->machine->frame.hard_fp_offset;
+      cfun->machine->frame.initial_adjust
+	= cfun->machine->frame.bytes_above_hard_fp;
       cfun->machine->frame.final_adjust
 	= cfun->machine->frame.frame_size - cfun->machine->frame.initial_adjust;
     }
@@ -5651,10 +5654,10 @@ aarch64_initial_elimination_offset (unsigned from, unsigned to)
   if (to == HARD_FRAME_POINTER_REGNUM)
     {
       if (from == ARG_POINTER_REGNUM)
-	return cfun->machine->frame.hard_fp_offset;
+	return cfun->machine->frame.bytes_above_hard_fp;
 
       if (from == FRAME_POINTER_REGNUM)
-	return cfun->machine->frame.hard_fp_offset
+	return cfun->machine->frame.bytes_above_hard_fp
 	       - cfun->machine->frame.bytes_above_locals;
     }
 
diff --git a/gcc/config/aarch64/aarch64.h b/gcc/config/aarch64/aarch64.h
index 79af237ada6..35ba9681e03 100644
--- a/gcc/config/aarch64/aarch64.h
+++ b/gcc/config/aarch64/aarch64.h
@@ -570,10 +570,10 @@ struct GTY (()) aarch64_frame
      STACK_BOUNDARY.  */
   HOST_WIDE_INT bytes_above_locals;
 
-  /* Offset from the base of the frame (incomming SP) to the
-     hard_frame_pointer.  This value is always a multiple of
+  /* The number of bytes between the hard_frame_pointer and the top of
+     the frame (the incomming SP).  This value is always a multiple of
      STACK_BOUNDARY.  */
-  HOST_WIDE_INT hard_fp_offset;
+  HOST_WIDE_INT bytes_above_hard_fp;
 
   /* The size of the frame.  This value is the offset from base of the
    * frame (incomming SP) to the stack_pointer.  This value is always
-- 
2.25.1

From 19776fcf06856ceff521f99a1ceddaf113cf0d09 Mon Sep 17 00:00:00 2001
From: Richard Sandiford <richard.sandiford@arm.com>
Date: Thu, 22 Jun 2023 22:26:30 +0100
Subject: [PATCH 5/7] aarch64: Tweak frame_size comment
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
To: gcc-patches@gcc.gnu.org

This patch fixes another case in which a value was described with
an “upside-down” view.

gcc/
	* config/aarch64/aarch64.h (aarch64_frame::frame_size): Tweak comment.
---
 gcc/config/aarch64/aarch64.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/gcc/config/aarch64/aarch64.h b/gcc/config/aarch64/aarch64.h
index 35ba9681e03..19b7082187a 100644
--- a/gcc/config/aarch64/aarch64.h
+++ b/gcc/config/aarch64/aarch64.h
@@ -575,9 +575,9 @@ struct GTY (()) aarch64_frame
      STACK_BOUNDARY.  */
   HOST_WIDE_INT bytes_above_hard_fp;
 
-  /* The size of the frame.  This value is the offset from base of the
-   * frame (incomming SP) to the stack_pointer.  This value is always
-   * a multiple of STACK_BOUNDARY.  */
+  /* The size of the frame, i.e. the number of bytes between the bottom
+     of the outgoing arguments and the incoming SP.  This value is always
+     a multiple of STACK_BOUNDARY.  */
   HOST_WIDE_INT frame_size;
 
   /* The size of the initial stack adjustment before saving callee-saves.  */
-- 
2.25.1

From 69c18301a2dea6dd686d4351ba3c095490707d16 Mon Sep 17 00:00:00 2001
From: Richard Sandiford <richard.sandiford@arm.com>
Date: Tue, 15 Aug 2023 19:05:30 +0100
Subject: [PATCH 6/7] Backport check-function-bodies support
To: gcc-patches@gcc.gnu.org

---
 gcc/testsuite/lib/scanasm.exp | 191 ++++++++++++++++++++++++++++++++++
 1 file changed, 191 insertions(+)

diff --git a/gcc/testsuite/lib/scanasm.exp b/gcc/testsuite/lib/scanasm.exp
index bab23e8e165..1103f86c602 100644
--- a/gcc/testsuite/lib/scanasm.exp
+++ b/gcc/testsuite/lib/scanasm.exp
@@ -514,3 +514,194 @@ proc scan-lto-assembler { args } {
     verbose "output_file: $output_file"
     dg-scan "scan-assembler" 1 $testcase $output_file $args
 }
+
+# Read assembly file FILENAME and store a mapping from function names
+# to function bodies in array RESULT.  FILENAME has already been uploaded
+# locally where necessary and is known to exist.
+
+proc parse_function_bodies { filename result } {
+    upvar $result up_result
+
+    # Regexp for the start of a function definition (name in \1).
+    set label {^([a-zA-Z_]\S+):$}
+
+    # Regexp for the end of a function definition.
+    set terminator {^\s*\.size}
+
+    # Regexp for lines that aren't interesting.
+    set fluff {^\s*(?:\.|//|@|$)}
+
+    set fd [open $filename r]
+    set in_function 0
+    while { [gets $fd line] >= 0 } {
+	if { [regexp $label $line dummy function_name] } {
+	    set in_function 1
+	    set function_body ""
+	} elseif { $in_function } {
+	    if { [regexp $terminator $line] } {
+		set up_result($function_name) $function_body
+		set in_function 0
+	    } elseif { ![regexp $fluff $line] } {
+		append function_body $line "\n"
+	    }
+	}
+    }
+    close $fd
+}
+
+# FUNCTIONS is an array that maps function names to function bodies.
+# Return true if it contains a definition of function NAME and if
+# that definition matches BODY_REGEXP.
+
+proc check_function_body { functions name body_regexp } {
+    upvar $functions up_functions
+
+    if { ![info exists up_functions($name)] } {
+	return 0
+    }
+    set fn_res [regexp "^$body_regexp\$" $up_functions($name)]
+    if { !$fn_res } {
+      verbose -log "body: $body_regexp"
+      verbose -log "against: $up_functions($name)"
+    }
+    return $fn_res
+}
+
+# Check the implementations of functions against expected output.  Used as:
+#
+# { dg-do { check-function-bodies PREFIX TERMINATOR[ OPTION[ SELECTOR]] } }
+#
+# See sourcebuild.texi for details.
+
+proc check-function-bodies { args } {
+    if { [llength $args] < 2 } {
+	error "too few arguments to check-function-bodies"
+    }
+    if { [llength $args] > 4 } {
+	error "too many arguments to check-function-bodies"
+    }
+
+    if { [llength $args] >= 3 } {
+	set required_flags [lindex $args 2]
+
+	upvar 2 dg-extra-tool-flags extra_tool_flags
+	set flags $extra_tool_flags
+
+	global torture_current_flags
+	if { [info exists torture_current_flags] } {
+	    append flags " " $torture_current_flags
+	}
+	foreach required_flag $required_flags {
+	    switch -- $required_flag {
+		target -
+		xfail {
+		    error "misplaced $required_flag in check-function-bodies"
+		}
+	    }
+	}
+	foreach required_flag $required_flags {
+	    if { ![regexp " $required_flag " $flags] } {
+		return
+	    }
+	}
+    }
+
+    set xfail_all 0
+    if { [llength $args] >= 4 } {
+	switch [dg-process-target [lindex $args 3]] {
+	    "S" { }
+	    "N" { return }
+	    "F" { set xfail_all 1 }
+	    "P" { }
+	}
+    }
+
+    set testcase [testname-for-summary]
+    # The name might include a list of options; extract the file name.
+    set filename [lindex $testcase 0]
+
+    global srcdir
+    set input_filename "$srcdir/$filename"
+    set output_filename "[file rootname [file tail $filename]].s"
+
+    set prefix [lindex $args 0]
+    set prefix_len [string length $prefix]
+    set terminator [lindex $args 1]
+    if { [string equal $terminator ""] } {
+	set terminator "*/"
+    }
+    set terminator_len [string length $terminator]
+
+    set have_bodies 0
+    if { [is_remote host] } {
+	remote_upload host "$filename"
+    }
+    if { [file exists $output_filename] } {
+	parse_function_bodies $output_filename functions
+	set have_bodies 1
+    } else {
+	verbose -log "$testcase: output file does not exist"
+    }
+
+    set count 0
+    set function_regexp ""
+    set label {^(\S+):$}
+
+    set lineno 1
+    set fd [open $input_filename r]
+    set in_function 0
+    while { [gets $fd line] >= 0 } {
+	if { [string equal -length $prefix_len $line $prefix] } {
+	    set line [string trim [string range $line $prefix_len end]]
+	    if { !$in_function } {
+		if { [regexp "^(.*?\\S)\\s+{(.*)}\$" $line dummy \
+			  line selector] } {
+		    set selector [dg-process-target $selector]
+		} else {
+		    set selector "P"
+		}
+		if { ![regexp $label $line dummy function_name] } {
+		    close $fd
+		    error "check-function-bodies: line $lineno does not have a function label"
+		}
+		set in_function 1
+		set function_regexp ""
+	    } elseif { [string equal $line "("] } {
+		append function_regexp "(?:"
+	    } elseif { [string equal $line "|"] } {
+		append function_regexp "|"
+	    } elseif { [string equal $line ")"] } {
+		append function_regexp ")"
+	    } elseif { [string equal $line "..."] } {
+		append function_regexp ".*"
+	    } else {
+		append function_regexp "\t" $line "\n"
+	    }
+	} elseif { [string equal -length $terminator_len $line $terminator] } {
+	    if { ![string equal $selector "N"] } {
+		if { $xfail_all || [string equal $selector "F"] } {
+		    setup_xfail "*-*-*"
+		}
+		set testname "$testcase check-function-bodies $function_name"
+		if { !$have_bodies } {
+		    unresolved $testname
+		} elseif { [check_function_body functions $function_name \
+				$function_regexp] } {
+		    pass $testname
+		} else {
+		    fail $testname
+		}
+	    }
+	    set in_function 0
+	    incr count
+	}
+	incr lineno
+    }
+    close $fd
+    if { $in_function } {
+	error "check-function-bodies: missing \"$terminator\""
+    }
+    if { $count == 0 } {
+	error "check-function-bodies: no matches found"
+    }
+}
-- 
2.25.1

From c2c772172f0478315ab94386ebf9963efd36eb75 Mon Sep 17 00:00:00 2001
From: Richard Sandiford <richard.sandiford@arm.com>
Date: Thu, 15 Jun 2023 19:16:52 +0100
Subject: [PATCH 7/7] aarch64: Make stack smash canary protect saved registers
To: gcc-patches@gcc.gnu.org

AArch64 normally puts the saved registers near the bottom of the frame,
immediately above any dynamic allocations.  But this means that a
stack-smash attack on those dynamic allocations could overwrite the
saved registers without needing to reach as far as the stack smash
canary.

The same thing could also happen for variable-sized arguments that are
passed by value, since those are allocated before a call and popped on
return.

This patch avoids that by putting the locals (and thus the canary) below
the saved registers when stack smash protection is active.

The patch fixes CVE-2023-4039.

gcc/
	* config/aarch64/aarch64.c (aarch64_save_regs_above_locals_p):
	New function.
	(aarch64_layout_frame): Use it to decide whether locals should
	go above or below the saved registers.
	(aarch64_expand_prologue): Update stack layout comment.
	Emit a stack tie after the final adjustment.

gcc/testsuite/
	* gcc.target/aarch64/stack-protector-8.c: New test.
	* gcc.target/aarch64/stack-protector-9.c: Likewise.
---
 gcc/config/aarch64/aarch64.c                  | 45 +++++++++-
 .../gcc.target/aarch64/stack-protector-8.c    | 86 +++++++++++++++++++
 .../gcc.target/aarch64/stack-protector-9.c    | 33 +++++++
 3 files changed, 161 insertions(+), 3 deletions(-)
 create mode 100644 gcc/testsuite/gcc.target/aarch64/stack-protector-8.c
 create mode 100644 gcc/testsuite/gcc.target/aarch64/stack-protector-9.c

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index e3c36abb1e3..8708b4fe4ea 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -2780,6 +2780,20 @@ aarch64_frame_pointer_required (void)
   return false;
 }
 
+/* Return true if the current function should save registers above
+   the locals area, rather than below it.  */
+
+static bool
+aarch64_save_regs_above_locals_p ()
+{
+  /* When using stack smash protection, make sure that the canary slot
+     comes between the locals and the saved registers.  Otherwise,
+     it would be possible for a carefully sized smash attack to change
+     the saved registers (particularly LR and FP) without reaching the
+     canary.  */
+  return crtl->stack_protect_guard;
+}
+
 /* Mark the registers that need to be saved by the callee and calculate
    the size of the callee-saved registers area and frame record (both FP
    and LR may be omitted).  */
@@ -2828,6 +2842,16 @@ aarch64_layout_frame (void)
 
   cfun->machine->frame.bytes_below_hard_fp = crtl->outgoing_args_size;
 
+  bool regs_at_top_p = aarch64_save_regs_above_locals_p ();
+
+  if (regs_at_top_p)
+    {
+      cfun->machine->frame.bytes_below_hard_fp += get_frame_size ();
+      cfun->machine->frame.bytes_below_hard_fp
+	= ROUND_UP (cfun->machine->frame.bytes_below_hard_fp,
+		    STACK_BOUNDARY / BITS_PER_UNIT);
+    }
+
   if (frame_pointer_needed)
     {
       /* FP and LR are placed in the linkage record.  */
@@ -2881,8 +2905,11 @@ aarch64_layout_frame (void)
   HOST_WIDE_INT varargs_and_saved_regs_size
     = offset + cfun->machine->frame.saved_varargs_size;
 
+  cfun->machine->frame.bytes_above_hard_fp = varargs_and_saved_regs_size;
+  if (!regs_at_top_p)
+    cfun->machine->frame.bytes_above_hard_fp += get_frame_size ();
   cfun->machine->frame.bytes_above_hard_fp
-    = ROUND_UP (varargs_and_saved_regs_size + get_frame_size (),
+    = ROUND_UP (cfun->machine->frame.bytes_above_hard_fp,
 		STACK_BOUNDARY / BITS_PER_UNIT);
 
   cfun->machine->frame.frame_size
@@ -2892,6 +2919,9 @@ aarch64_layout_frame (void)
 
   cfun->machine->frame.bytes_above_locals
     = cfun->machine->frame.saved_varargs_size;
+  if (regs_at_top_p)
+    cfun->machine->frame.bytes_above_locals
+      += cfun->machine->frame.saved_regs_size;
 
   cfun->machine->frame.initial_adjust = 0;
   cfun->machine->frame.final_adjust = 0;
@@ -3537,10 +3567,10 @@ aarch64_set_handled_components (sbitmap components)
 	|  for register varargs         |
 	|                               |
 	+-------------------------------+
-	|  local variables              | <-- frame_pointer_rtx
+	|  local variables (1)          | <-- frame_pointer_rtx
 	|                               |
 	+-------------------------------+
-	|  padding0                     | \
+	|  padding (1)                  | \
 	+-------------------------------+  |
 	|  callee-saved registers       |  | frame.saved_regs_size
 	+-------------------------------+  |
@@ -3548,6 +3578,10 @@ aarch64_set_handled_components (sbitmap components)
 	+-------------------------------+  |
 	|  FP'                          | / <- hard_frame_pointer_rtx (aligned)
         +-------------------------------+
+	|  local variables (2)          |
+	+-------------------------------+
+	|  padding (2)                  |
+	+-------------------------------+
 	|  dynamic allocation           |
 	+-------------------------------+
 	|  padding                      |
@@ -3557,6 +3591,9 @@ aarch64_set_handled_components (sbitmap components)
 	+-------------------------------+
 	|                               | <-- stack_pointer_rtx (aligned)
 
+   The regions marked (1) and (2) are mutually exclusive.  (2) is used
+   when aarch64_save_regs_above_locals_p is true.
+
    Dynamic stack allocations via alloca() decrease stack_pointer_rtx
    but leave frame_pointer_rtx and hard_frame_pointer_rtx
    unchanged.  */
@@ -3626,6 +3663,8 @@ aarch64_expand_prologue (void)
   aarch64_save_callee_saves (DFmode, callee_offset, V0_REGNUM, V31_REGNUM,
 			     callee_adjust != 0 || frame_pointer_needed);
   aarch64_sub_sp (IP1_REGNUM, final_adjust, !frame_pointer_needed);
+  if (frame_pointer_needed && final_adjust != 0)
+    emit_insn (gen_stack_tie (stack_pointer_rtx, hard_frame_pointer_rtx));
 }
 
 /* Return TRUE if we can use a simple_return insn.
diff --git a/gcc/testsuite/gcc.target/aarch64/stack-protector-8.c b/gcc/testsuite/gcc.target/aarch64/stack-protector-8.c
new file mode 100644
index 00000000000..2575abbec73
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/stack-protector-8.c
@@ -0,0 +1,86 @@
+/* { dg-options " -O -fstack-protector-strong" } */
+/* { dg-final { check-function-bodies "**" "" } } */
+
+void g(void *);
+
+/*
+** test1:
+**	sub	sp, sp, #304
+**	stp	x29, x30, \[sp, #?272\]
+**	add	x29, sp, #?272
+**	str	(x[0-9]+), \[sp, #?288\]
+**	...
+**	ldr	(x[0-9]+), \[\1\]
+**	str	\2, \[(?:sp, #?264|x29, #?-8)\]
+**	mov	\2, *0
+** (
+**	add	x0, sp, #?8
+** |
+**	sub	x0, x29, #?264
+** )
+**	bl	g
+**	...
+**	ldr	x[0-9]+, \[\1\]
+**	...
+** (
+**	bne	.*
+** |
+**	cbnz	.*
+** )
+**	...
+**	ldr	\1, \[sp, #?288\]
+**	ldp	x29, x30, \[sp, #?272\]
+**	add	sp, sp, #?304
+**	ret
+**	bl	__stack_chk_fail
+*/
+int test1() {
+  int y[0x40];
+  g(y);
+  return 1;
+}
+
+/*
+** test2:
+**	stp	x29, x30, \[sp, #?-32\]!
+** (
+**	mov	x29, sp
+** |
+**	add	x29, sp, #?0
+** )
+**	str	(x[0-9]+), \[sp, #?16\]
+**	sub	sp, sp, #1040
+**	...
+**	ldr	(x[0-9]+), \[\1\]
+**	str	\2, \[(?:sp, #?1032|x29, #?-8)\]
+**	mov	\2, *0
+** (
+**	add	x0, sp, #?8
+** |
+**	sub	x0, x29, #?1032
+** )
+**	bl	g
+**	...
+**	ldr	x[0-9]+, \[\1\]
+**	...
+** (
+**	bne	.*
+** |
+**	cbnz	.*
+** )
+**	...
+** (
+**	add	sp, sp, #?1040
+** |
+**	add	sp, x29, #?0
+** )
+**	ldr	\1, \[sp, #?16\]
+**	ldp	x29, x30, \[sp\], #?32
+**	ret
+**	bl	__stack_chk_fail
+*/
+int test2() {
+  int y[0x100];
+  g(y);
+  return 1;
+}
diff --git a/gcc/testsuite/gcc.target/aarch64/stack-protector-9.c b/gcc/testsuite/gcc.target/aarch64/stack-protector-9.c
new file mode 100644
index 00000000000..1d267343806
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/stack-protector-9.c
@@ -0,0 +1,33 @@
+/* { dg-options "-O2 -mcpu=cortex-a73 -fstack-protector-all" } */
+/* { dg-final { check-function-bodies "**" "" } } */
+
+/*
+** main:
+**	...
+**	stp	x29, x30, \[sp, #?-[0-9]+\]!
+**	...
+**	sub	sp, sp, #[0-9]+
+**	...
+**	str	x[0-9]+, \[x29, #?-8\]
+**	...
+*/
+int f(const char *);
+void g(void *);
+int main(int argc, char* argv[])
+{
+  int a;
+  int b;
+  char c[2+f(argv[1])];
+  int d[0x100];
+  char y;
+
+  y=42; a=4; b=10;
+  c[0] = 'h'; c[1] = '\0';
+
+  c[f(argv[2])] = '\0';
+
+  __builtin_printf("%d %d\n%s\n", a, b, c);
+  g(d);
+
+  return 0;
+}
-- 
2.25.1

Places

File gcc7-aarch64-bsc1214052.patch of Package cross-aarch64-gcc7 (Revision 222157e82135407d7ae8f1ddc13876bc)

Places