[PATCH 1/2] Fix uninitialized field in expand_operand.

[PATCH 1/2] Fix uninitialized field in expand_operand.

[apinski]

From: Andrew Pinski <apinski@marvell.com>

Commit g:f96bf49a0 added the target field to expand_operand.
But it leaves it uninitialized when doing a full initialization
inside create_expand_operand.  This fixes the problem and improves
the code generation inside create_expand_operand too.

OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.

ChangeLog:
* optabs.h (create_expand_operand): Initialize target field also.

Change-Id: Ib653fbfbb2b0709970db87fb94de14b59758bc6c
---
 gcc/optabs.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/gcc/optabs.h b/gcc/optabs.h
index 07bdc56586e..5bd19503a0a 100644
--- a/gcc/optabs.h
+++ b/gcc/optabs.h
@@ -78,6 +78,7 @@ create_expand_operand (class expand_operand *op,
 {
   op->type = type;
   op->unsigned_p = unsigned_p;
+  op->target = 0;
   op->unused = 0;
   op->mode = mode;
   op->value = value;
-- 
2.17.1

[PATCH 2/2] Uninitialized padding in struct _dep.

[apinski]

From: Andrew Pinski <apinski@marvell.com>

In struct _dep, there is an implicit padding of 4bits.  This
bit-field padding is uninitialized when init_dep_1 is being called.
This means we access uninitialized memory but never use it for
anything.  Adding an unused bit-field field and initializing it
in init_dep_1 will improve code generation also as we initialize
the whole 32bits now rather than just part of it.

OK?  Bootstrapped and tested on x86_64-linux-gnu.

Thanks,
Andrew Pinski

ChangeLog:
* sched-int.h (_dep): Add unused bit-field field for the padding.
* sched-deps.c (init_dep_1): Init unused field.

Change-Id: I27000323e728f8a73189426e0b9a98c5235b8c55
---
 gcc/sched-deps.c | 1 +
 gcc/sched-int.h  | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/gcc/sched-deps.c b/gcc/sched-deps.c
index 9182aba5588..331af5ffdb3 100644
--- a/gcc/sched-deps.c
+++ b/gcc/sched-deps.c
@@ -101,6 +101,7 @@ init_dep_1 (dep_t dep, rtx_insn *pro, rtx_insn *con, enum reg_note type, ds_t ds
   DEP_NONREG (dep) = 0;
   DEP_MULTIPLE (dep) = 0;
   DEP_REPLACE (dep) = NULL;
+  dep->unused = 0;
 }
 
 /* Init DEP with the arguments.
diff --git a/gcc/sched-int.h b/gcc/sched-int.h
index 833b552a340..a847f876e65 100644
--- a/gcc/sched-int.h
+++ b/gcc/sched-int.h
@@ -238,6 +238,8 @@ struct _dep
   /* Cached cost of the dependency.  Make sure to update UNKNOWN_DEP_COST
      when changing the size of this field.  */
   int cost:20;
+
+  unsigned unused:4;
 };
 
 #define UNKNOWN_DEP_COST ((int) ((unsigned int) -1 << 19))
-- 
2.17.1

Re: [PATCH 1/2] Fix uninitialized field in expand_operand.

[Richard Biener]

On January 16, 2020 6:08:48 AM GMT+01:00, apinski@marvell.com wrote:
>From: Andrew Pinski <apinski@marvell.com>
>
>Commit g:f96bf49a0 added the target field to expand_operand.
>But it leaves it uninitialized when doing a full initialization
>inside create_expand_operand.  This fixes the problem and improves
>the code generation inside create_expand_operand too.
>
>OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.

OK. 

Richard. 

>ChangeLog:
>* optabs.h (create_expand_operand): Initialize target field also.
>
>Change-Id: Ib653fbfbb2b0709970db87fb94de14b59758bc6c
>---
> gcc/optabs.h | 1 +
> 1 file changed, 1 insertion(+)
>
>diff --git a/gcc/optabs.h b/gcc/optabs.h
>index 07bdc56586e..5bd19503a0a 100644
>--- a/gcc/optabs.h
>+++ b/gcc/optabs.h
>@@ -78,6 +78,7 @@ create_expand_operand (class expand_operand *op,
> {
>   op->type = type;
>   op->unsigned_p = unsigned_p;
>+  op->target = 0;
>   op->unused = 0;
>   op->mode = mode;
>   op->value = value;

Re: [PATCH 2/2] Uninitialized padding in struct _dep.

[Richard Biener]

On January 16, 2020 6:08:49 AM GMT+01:00, apinski@marvell.com wrote:
>From: Andrew Pinski <apinski@marvell.com>
>
>In struct _dep, there is an implicit padding of 4bits.  This
>bit-field padding is uninitialized when init_dep_1 is being called.
>This means we access uninitialized memory but never use it for
>anything.  Adding an unused bit-field field and initializing it
>in init_dep_1 will improve code generation also as we initialize
>the whole 32bits now rather than just part of it.
>
>OK?  Bootstrapped and tested on x86_64-linux-gnu.

OK. 

Richard. 

>Thanks,
>Andrew Pinski
>
>ChangeLog:
>* sched-int.h (_dep): Add unused bit-field field for the padding.
>* sched-deps.c (init_dep_1): Init unused field.
>
>Change-Id: I27000323e728f8a73189426e0b9a98c5235b8c55
>---
> gcc/sched-deps.c | 1 +
> gcc/sched-int.h  | 2 ++
> 2 files changed, 3 insertions(+)
>
>diff --git a/gcc/sched-deps.c b/gcc/sched-deps.c
>index 9182aba5588..331af5ffdb3 100644
>--- a/gcc/sched-deps.c
>+++ b/gcc/sched-deps.c
>@@ -101,6 +101,7 @@ init_dep_1 (dep_t dep, rtx_insn *pro, rtx_insn
>*con, enum reg_note type, ds_t ds
>   DEP_NONREG (dep) = 0;
>   DEP_MULTIPLE (dep) = 0;
>   DEP_REPLACE (dep) = NULL;
>+  dep->unused = 0;
> }
> 
> /* Init DEP with the arguments.
>diff --git a/gcc/sched-int.h b/gcc/sched-int.h
>index 833b552a340..a847f876e65 100644
>--- a/gcc/sched-int.h
>+++ b/gcc/sched-int.h
>@@ -238,6 +238,8 @@ struct _dep
>/* Cached cost of the dependency.  Make sure to update UNKNOWN_DEP_COST
>      when changing the size of this field.  */
>   int cost:20;
>+
>+  unsigned unused:4;
> };
> 
> #define UNKNOWN_DEP_COST ((int) ((unsigned int) -1 << 19))