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* [PATCH] include MEM_REF type in tree dumps (PR 90676)
@ 2019-06-01 15:53 Martin Sebor
  2019-06-01 16:16 ` Martin Sebor
  2019-06-03  8:36 ` Richard Biener
  0 siblings, 2 replies; 23+ messages in thread
From: Martin Sebor @ 2019-06-01 15:53 UTC (permalink / raw)
  To: gcc-patches

[-- Attachment #1: Type: text/plain, Size: 1338 bytes --]

I spent a bunch of time the other day trying to understand why
the second of the two assignments below to a char array was
apparently not being done by trunk

   a[0] = 1;
   a[1] = 0;

The optimized GIMPLE dump simply shows:

   MEM[(char *)&a] = 1;

when in the past it showed:

   MEM[(char[2] *)&a2] = 1;

After some debugging I figured out that this is the result of
the store merging pass transforming the two assignments into
one:

   *(short int *)a = 1;

and the MEM_REF dump mentioning only the type of the second
operand and not the type of the access.

To avoid this confusion the attached patch adds to the dump
a cast to the MEM_REF type for accesses whose size is not equal
to the size of the operand (when the sizes are the same no new
cast is prepended).  The effect is that with store merging in
effect, the dump for the above becomes

   MEM[(short int *)(char *)&a] = 1;

This should make both the size and the type of the access clear
and help avoid the confusion.  The output isn't the same as in
earlier releases because because the access really is done via
a short pointer and not as an array of char.

There is more detail in MEM_REF that could be included here but
it seems that the size of the access is essential to interpreting
the dumps.

Tested on x86_64-linux with only minimal testsuite fallout.

Martin

[-- Attachment #2: gcc-90676.diff --]
[-- Type: text/x-patch, Size: 8293 bytes --]

diff --git a/gcc/testsuite/g++.dg/tree-ssa/pr19807.C b/gcc/testsuite/g++.dg/tree-ssa/pr19807.C
index cbe06b4ce62..08e0dd13115 100644
--- a/gcc/testsuite/g++.dg/tree-ssa/pr19807.C
+++ b/gcc/testsuite/g++.dg/tree-ssa/pr19807.C
@@ -11,7 +11,8 @@ void foo(void)
 	z = 1 + &a[1];
 }
 
-/* { dg-final { scan-tree-dump-times "&MEM\\\[\\\(void .\\\)&a \\\+ 8B\\\]" 3 "optimized" } } */
+/* { dg-final { scan-tree-dump-times "&MEM\\\[\\\(void .\\\)&a \\\+ 8B\\\]" 3 "optimized" { target { ! store_merge } } } }
+   { dg-final { scan-tree-dump-times "&MEM\\\[\\(int \\*\\)\\\(void .\\\)&a \\\+ 8B\\\]" 3 "optimized" { target { store_merge } } } } */
 
 
 void bar(int i)
diff --git a/gcc/testsuite/g++.dg/tree-ssa/ssa-dse-1.C b/gcc/testsuite/g++.dg/tree-ssa/ssa-dse-1.C
index 1fd8dec99e9..da9fc3b9c6a 100644
--- a/gcc/testsuite/g++.dg/tree-ssa/ssa-dse-1.C
+++ b/gcc/testsuite/g++.dg/tree-ssa/ssa-dse-1.C
@@ -97,5 +97,5 @@ int main()
 }
 
 
-/* { dg-final { scan-tree-dump-times "MEM\\\[\\(struct FixBuf \\*\\)&<retval> \\+ \[0-9\]+B\\\] = {}" 1 "dse1" } } */
-
+/* { dg-final { scan-tree-dump-times "MEM\\\[\\(struct FixBuf \\*\\)&<retval> \\+ \[0-9\]+B\\\] = {}" 1 "dse1" { target { ! store_merge } } } }
+   { dg-final { scan-tree-dump-times "MEM\\\[\\(char\\\[176] \\*\\)\\(struct FixBuf \\*\\)&<retval> \\+ \[0-9\]+B\\\] = {}" 1 "dse1" { target { store_merge } } } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/dump-6.c b/gcc/testsuite/gcc.dg/tree-ssa/dump-6.c
new file mode 100644
index 00000000000..8b4a51c6cbf
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/dump-6.c
@@ -0,0 +1,37 @@
+/* PR middle-end/90676 - default GIMPLE dumps lack information
+   { dg-do compile }
+   { dg-options "-O2 -fdump-tree-store-merging" }
+   { dg-require-effective-target int32plus }
+   { dg-require-effective-target store_merge } */
+
+
+extern char a2[2];
+
+void f2 (void)
+{
+  a2[0] = 1;
+  a2[1] = 0;
+}
+
+extern char a4[4];
+
+void f4 (void)
+{
+  a4[0] = 1;
+  a4[1] = 0;
+  a4[2] = 0;
+  a4[3] = 0;
+}
+
+extern char a8[8];
+
+void f8 (void)
+{
+  a8[0] = 1;
+  for (int i = 1; i != 8; ++i)
+    a8[i] = 0;
+}
+
+/* { dg-final { scan-tree-dump "MEM\\\[\\(unsigned short \\*\\)\\(char \\*\\)\\&a2] = " "store-merging"} }
+   { dg-final { scan-tree-dump "MEM\\\[\\(unsigned int \\*\\)\\(char \\*\\)\\&a4] = " "store-merging"} }
+   { dg-final { scan-tree-dump "MEM\\\[\\(unsigned long \\*\\)\\(char \\*\\)\\&a8] = " "store-merging"} } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr30375.c b/gcc/testsuite/gcc.dg/tree-ssa/pr30375.c
index 4494a2b0bd6..1d47e4c39eb 100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/pr30375.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr30375.c
@@ -22,5 +22,6 @@ void test_signed_msg_encoding(void)
     f();
 }
 
-/* { dg-final { scan-tree-dump-times "MEM\\\[\\(struct _s \\*\\)&signInfo \\+ \[0-9\]+B\\\] = {}" 1 "dse1" } } */
+/* { dg-final { scan-tree-dump-times "MEM\\\[\\(struct _s \\*\\)&signInfo \\+ \[0-9\]+B\\\] = {}" 1 "dse1" { target { ! store_merge } } } }
+   { dg-final { scan-tree-dump-times "MEM\\\[\\(char\\\[8] \\*\\)\\(struct _s \\*\\)&signInfo \\+ \[0-9\]+B\\\] = {}" 1 "dse1" { target { store_merge } } } } */
 
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/slsr-27.c b/gcc/testsuite/gcc.dg/tree-ssa/slsr-27.c
index 35b3d00ee44..ea9aad9c4cc 100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/slsr-27.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/slsr-27.c
@@ -19,4 +19,5 @@ f (struct x *p, unsigned int n)
 /* { dg-final { scan-tree-dump-times "\\* 4;" 1 "dom3" { target { int32 } } } } */
 /* { dg-final { scan-tree-dump-times "\\* 2;" 1 "dom3" { target { int16 } } } } */
 /* { dg-final { scan-tree-dump-times "p_\\d\+\\(D\\) \\+ \[^\r\n\]*_\\d\+;" 1 "dom3" } } */
-/* { dg-final { scan-tree-dump-times "MEM\\\[\\(struct x \\*\\)\[^\r\n\]*_\\d\+" 3 "dom3" } } */
+/* { dg-final { scan-tree-dump-times "MEM\\\[\\(struct x \\*\\)\[^\r\n\]*_\\d\+" 3 "dom3" { target { ! store_merge } } } } */
+/* { dg-final { scan-tree-dump-times "MEM\\\[\\(int \\*\\)\\(struct x \\*\\)\[^\r\n\]*_\\d\+" 3 "dom3" { target { store_merge } } } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/slsr-28.c b/gcc/testsuite/gcc.dg/tree-ssa/slsr-28.c
index 732d2324db5..37526a3d9fb 100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/slsr-28.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/slsr-28.c
@@ -23,4 +23,5 @@ f (struct x *p, unsigned int n)
 /* { dg-final { scan-tree-dump-times "\\* 4;" 1 "dom3" { target { int32 } } } } */
 /* { dg-final { scan-tree-dump-times "\\* 2;" 1 "dom3" { target { int16 } } } } */
 /* { dg-final { scan-tree-dump-times "p_\\d\+\\(D\\) \\+ \[^\r\n\]*_\\d\+" 1 "dom3" } } */
-/* { dg-final { scan-tree-dump-times "MEM\\\[\\(struct x \\*\\)\[^\r\n\]*_\\d\+" 9 "dom3" } } */
+/* { dg-final { scan-tree-dump-times "MEM\\\[\\(struct x \\*\\)\[^\r\n\]*_\\d\+" 9 "dom3" { target { ! store_merge } } } } */
+/* { dg-final { scan-tree-dump-times "MEM\\\[\\(int \\*\\)\\(struct x \\*\\)\[^\r\n\]*_\\d\+" 9 "dom3" { target { store_merge } } } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/slsr-29.c b/gcc/testsuite/gcc.dg/tree-ssa/slsr-29.c
index a22cc7906da..8499f2bd28c 100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/slsr-29.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/slsr-29.c
@@ -25,4 +25,5 @@ f (struct x *p, unsigned int n)
 /* { dg-final { scan-tree-dump-times "\\* 4;" 1 "dom3" { target { int32 } } } } */
 /* { dg-final { scan-tree-dump-times "\\* 2;" 1 "dom3" { target { int16 } } } } */
 /* { dg-final { scan-tree-dump-times "p_\\d\+\\(D\\) \\+ \[^\r\n\]*_\\d\+" 1 "dom3" } } */
-/* { dg-final { scan-tree-dump-times "MEM\\\[\\(struct x \\*\\)\[^\r\n\]*_\\d\+" 9 "dom3" } } */
+/* { dg-final { scan-tree-dump-times "MEM\\\[\\(struct x \\*\\)\[^\r\n\]*_\\d\+" 9 "dom3" { target { ! store_merge } } } } */
+/* { dg-final { scan-tree-dump-times "MEM\\\[\\(int \\*\\)\\(struct x \\*\\)\[^\r\n\]*_\\d\+" 9 "dom3" { target { store_merge } } } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-dse-24.c b/gcc/testsuite/gcc.dg/tree-ssa/ssa-dse-24.c
index 282194c1e32..709adce32bf 100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/ssa-dse-24.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-dse-24.c
@@ -59,4 +59,5 @@ void foo(int prec,
     bar (&info);
 }
 
-/* { dg-final { scan-tree-dump-times "MEM\\\[\\(struct printf_info \\*\\)&info \\+ \[0-9\]+B\\\] = {}" 1 "dse1" } } */
+/* { dg-final { scan-tree-dump-times "MEM\\\[\\(struct printf_info \\*\\)&info \\+ \[0-9\]+B\\\] = {}" 1 "dse1" { target { ! store_merge } } } }
+   { dg-final { scan-tree-dump-times "MEM\\\[\\(char\\\[4] \\*\\)\\(struct printf_info \\*\\)&info \\+ \[0-9\]+B\\\] = {}" 1 "dse1" { target { store_merge } } } } */
diff --git a/gcc/tree-pretty-print.c b/gcc/tree-pretty-print.c
index 4ba9170ddd3..649c81e06cd 100644
--- a/gcc/tree-pretty-print.c
+++ b/gcc/tree-pretty-print.c
@@ -1690,21 +1690,32 @@ dump_generic_node (pretty_printer *pp, tree node, int spc, dump_flags_t flags,
 	  }
 	else
 	  {
-	    tree ptype;
-
 	    pp_string (pp, "MEM[");
+	    tree nodetype = TREE_TYPE (node);
+	    tree op0 = TREE_OPERAND (node, 0);
+	    tree op1 = TREE_OPERAND (node, 1);
+	    tree op1type = TYPE_MAIN_VARIANT (TREE_TYPE (op1));
+
+	    if (!tree_int_cst_equal (TYPE_SIZE (nodetype),
+				     TYPE_SIZE (TREE_TYPE (op1type))))
+	      {
+		/* If the size of the type of the operand is not the same
+		   as the size of the MEM_REF expression include a cast
+		   to a pointer to the type of the latter to make it clear
+		   how many bytes of memory are being accessed.  */
+		pp_left_paren (pp);
+		dump_generic_node (pp, nodetype, spc, flags | TDF_SLIM, false);
+		pp_string (pp, " *)");
+	      }
+
 	    pp_left_paren (pp);
-	    ptype = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (node, 1)));
-	    dump_generic_node (pp, ptype,
-			       spc, flags | TDF_SLIM, false);
+	    dump_generic_node (pp, op1type, spc, flags | TDF_SLIM, false);
 	    pp_right_paren (pp);
-	    dump_generic_node (pp, TREE_OPERAND (node, 0),
-			       spc, flags, false);
-	    if (!integer_zerop (TREE_OPERAND (node, 1)))
+	    dump_generic_node (pp, op0, spc, flags, false);
+	    if (!integer_zerop (op1))
 	      {
 		pp_string (pp, " + ");
-		dump_generic_node (pp, TREE_OPERAND (node, 1),
-				   spc, flags, false);
+		dump_generic_node (pp, op1, spc, flags, false);
 	      }
 	    if ((flags & TDF_ALIAS)
 		&& MR_DEPENDENCE_CLIQUE (node) != 0)

^ permalink raw reply	[flat|nested] 23+ messages in thread
end of thread, other threads:[~2019-06-14  8:51 UTC | newest]

Thread overview: 23+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-06-01 15:53 [PATCH] include MEM_REF type in tree dumps (PR 90676) Martin Sebor
2019-06-01 16:16 ` Martin Sebor
2019-06-03  8:36 ` Richard Biener
2019-06-03  8:57   ` Jakub Jelinek
2019-06-03 10:35     ` Richard Biener
2019-06-03 15:13       ` Martin Sebor
2019-06-04 10:58         ` Richard Biener
2019-06-10 19:23           ` Martin Sebor
2019-06-10 19:29             ` Jakub Jelinek
2019-06-10 20:37               ` Martin Sebor
2019-06-11 10:43                 ` Richard Biener
2019-06-12 21:34                   ` Rainer Orth
2019-06-12 21:47                     ` Martin Sebor
2019-06-13  9:04                       ` Rainer Orth
2019-06-13 10:45                         ` Jakub Jelinek
2019-06-13 11:18                           ` Rainer Orth
2019-06-13 11:18                           ` Richard Biener
2019-06-13 15:30                           ` Martin Sebor
2019-06-13 15:34                             ` Jakub Jelinek
2019-06-13 15:50                               ` Martin Sebor
2019-06-13 15:54                                 ` Jakub Jelinek
2019-06-14  7:44                                   ` Richard Biener
2019-06-14  8:51                                     ` Jan Hubicka

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