[binutils-gdb] sframe: gas: libsframe: define constants and remove magic numbers

[binutils-gdb] sframe: gas: libsframe: define constants and remove magic numbers

[Indu Bhagat]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=3f107464e35cf63a529358a1c240821b30c35d2b

commit 3f107464e35cf63a529358a1c240821b30c35d2b
Author: Indu Bhagat <indu.bhagat@oracle.com>
Date:   Fri Dec 9 10:23:07 2022 -0800

    sframe: gas: libsframe: define constants and remove magic numbers
    
    Define constants in sframe.h for the various limits associated with the
    range of offsets that can be encoded in the start address of an SFrame
    FRE. E.g., sframe_frame_row_entry_addr1 is used when start address
    offset can be encoded as 1-byte unsigned value.
    
    Update the code in gas to use these defined constants as it checks for
    these limits, and remove the usage of magic numbers.
    
    ChangeLog:
    
            * gas/sframe-opt.c (sframe_estimate_size_before_relax):
            (sframe_convert_frag): Do not use magic numbers.
            * libsframe/sframe.c (sframe_calc_fre_type): Likewise.
    
    include/ChangeLog:
    
            * sframe.h (SFRAME_FRE_TYPE_ADDR1_LIMIT): New constant.
            (SFRAME_FRE_TYPE_ADDR2_LIMIT): Likewise.
            (SFRAME_FRE_TYPE_ADDR4_LIMIT): Likewise.

Diff:
---
 gas/sframe-opt.c   | 12 ++++++------
 include/sframe.h   | 15 +++++++++++++++
 libsframe/sframe.c |  6 +++---
 3 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/gas/sframe-opt.c b/gas/sframe-opt.c
index c17fd6b8332..6901aa82a77 100644
--- a/gas/sframe-opt.c
+++ b/gas/sframe-opt.c
@@ -53,9 +53,9 @@ sframe_estimate_size_before_relax (fragS *frag)
       widthS = exp->X_op_symbol;
       width = resolve_symbol_value (widthS);
 
-      if (width < 0x100)
+      if (width < SFRAME_FRE_TYPE_ADDR1_LIMIT)
 	ret = 1;
-      else if (width < 0x10000)
+      else if (width < SFRAME_FRE_TYPE_ADDR2_LIMIT)
 	ret = 2;
       else
 	ret = 4;
@@ -109,9 +109,9 @@ sframe_convert_frag (fragS *frag)
     {
       fsizeS = frag->fr_symbol;
       fsize = resolve_symbol_value (fsizeS);
-      if (fsize < 0x100)
+      if (fsize < SFRAME_FRE_TYPE_ADDR1_LIMIT)
 	func_info = SFRAME_FRE_TYPE_ADDR1;
-      else if (fsize < 0x10000)
+      else if (fsize < SFRAME_FRE_TYPE_ADDR2_LIMIT)
 	func_info = SFRAME_FRE_TYPE_ADDR2;
       else
 	func_info = SFRAME_FRE_TYPE_ADDR4;
@@ -133,11 +133,11 @@ sframe_convert_frag (fragS *frag)
       switch (frag->fr_subtype & 7)
 	{
 	case 1:
-	  gas_assert (fsize < 0x100);
+	  gas_assert (fsize < SFRAME_FRE_TYPE_ADDR1_LIMIT);
 	  frag->fr_literal[frag->fr_fix] = diff;
 	  break;
 	case 2:
-	  gas_assert (fsize < 0x10000);
+	  gas_assert (fsize < SFRAME_FRE_TYPE_ADDR2_LIMIT);
 	  md_number_to_chars (frag->fr_literal + frag->fr_fix, diff, 2);
 	  break;
 	case 4:
diff --git a/include/sframe.h b/include/sframe.h
index 7e167bf4dbe..03a2d75dfd3 100644
--- a/include/sframe.h
+++ b/include/sframe.h
@@ -273,6 +273,7 @@ typedef struct sframe_fre_info
     fi
 */
 
+/* Used when SFRAME_FRE_TYPE_ADDR1 is specified as FRE type.  */
 typedef struct sframe_frame_row_entry_addr1
 {
   /* Start address of the frame row entry.  Encoded as an 1-byte unsigned
@@ -281,6 +282,11 @@ typedef struct sframe_frame_row_entry_addr1
   sframe_fre_info sfre_info;
 } ATTRIBUTE_PACKED sframe_frame_row_entry_addr1;
 
+/* Upper limit of start address in sframe_frame_row_entry_addr1
+   is 0x100 (not inclusive).  */
+#define SFRAME_FRE_TYPE_ADDR1_LIMIT  ((SFRAME_FRE_TYPE_ADDR1 + 1) * 8)
+
+/* Used when SFRAME_FRE_TYPE_ADDR2 is specified as FRE type.  */
 typedef struct sframe_frame_row_entry_addr2
 {
   /* Start address of the frame row entry.  Encoded as an 2-byte unsigned
@@ -289,6 +295,11 @@ typedef struct sframe_frame_row_entry_addr2
   sframe_fre_info sfre_info;
 } ATTRIBUTE_PACKED sframe_frame_row_entry_addr2;
 
+/* Upper limit of start address in sframe_frame_row_entry_addr2
+   is 0x10000 (not inclusive).  */
+#define SFRAME_FRE_TYPE_ADDR2_LIMIT  ((SFRAME_FRE_TYPE_ADDR2 * 2) * 8)
+
+/* Used when SFRAME_FRE_TYPE_ADDR4 is specified as FRE type.  */
 typedef struct sframe_frame_row_entry_addr4
 {
   /* Start address of the frame row entry.  Encoded as a 4-byte unsigned
@@ -297,6 +308,10 @@ typedef struct sframe_frame_row_entry_addr4
   sframe_fre_info sfre_info;
 } ATTRIBUTE_PACKED sframe_frame_row_entry_addr4;
 
+/* Upper limit of start address in sframe_frame_row_entry_addr2
+   is 0x100000000 (not inclusive).  */
+#define SFRAME_FRE_TYPE_ADDR4_LIMIT  ((SFRAME_FRE_TYPE_ADDR4 * 2) * 8)
+
 #ifdef	__cplusplus
 }
 #endif
diff --git a/libsframe/sframe.c b/libsframe/sframe.c
index 6e0eb7b6511..64fa9078d62 100644
--- a/libsframe/sframe.c
+++ b/libsframe/sframe.c
@@ -572,11 +572,11 @@ unsigned int
 sframe_calc_fre_type (unsigned int func_size)
 {
   unsigned int fre_type = 0;
-  if (func_size <= 0xff)
+  if (func_size < SFRAME_FRE_TYPE_ADDR1_LIMIT)
     fre_type = SFRAME_FRE_TYPE_ADDR1;
-  else if (func_size <= 0xffff)
+  else if (func_size < SFRAME_FRE_TYPE_ADDR2_LIMIT)
     fre_type = SFRAME_FRE_TYPE_ADDR2;
-  else if (func_size <= 0xffffffff)
+  else if (func_size < SFRAME_FRE_TYPE_ADDR4_LIMIT)
     fre_type = SFRAME_FRE_TYPE_ADDR4;
   return fre_type;
 }