Fix PR81422[aarch64] internal compiler error: in update_equiv_regs, at ira.c:3425

Hi,

This patch fixes the aarch64 bug 81422 
https://gcc.gnu.org/PR81422

Before adding REG_EQUIV notes in the TLS symbol handling code,
we should check whether the "dest" is a REG or NOT (sometimes,
it's a SUBREG as in this bug). Only when the “dest” is a REG, the note
will be added.

a new small testing case is added. 

this change has been tested on aarch64-unknown-linux-gnu with no regression. 

Thanks!

Qing

Ping

https://www.mail-archive.com/gcc-patches@gcc.gnu.org/msg173877.html

> On Sep 19, 2017, at 2:22 PM, Qing Zhao <qing.zhao@oracle.com> wrote:
> 
> Hi,
> 
> This patch fixes the aarch64 bug 81422 
> https://gcc.gnu.org/PR81422
> 
> Before adding REG_EQUIV notes in the TLS symbol handling code,
> we should check whether the "dest" is a REG or NOT (sometimes,
> it's a SUBREG as in this bug). Only when the “dest” is a REG, the note
> will be added.
> 
> a new small testing case is added. 
> 
> this change has been tested on aarch64-unknown-linux-gnu with no regression. 
> 
> Thanks!
> 
> Qing
> 
> 
> ===============
> 
> gcc/ChangeLog:
> 
>       * config/aarch64/aarch64.c (aarch64_load_symref_appropriately):
>       check whether the dest is REG before adding REG_EQUIV note.
> 
> gcc/testsuite/ChangeLog:
> 
>       PR target/81422
>       * gcc.target/aarch64/pr81422.C: New test.
> 
> ---
> gcc/config/aarch64/aarch64.c               | 12 ++++++++----
> gcc/testsuite/gcc.target/aarch64/pr81422.C | 15 +++++++++++++++
> 2 files changed, 23 insertions(+), 4 deletions(-)
> create mode 100644 gcc/testsuite/gcc.target/aarch64/pr81422.C
> 
> diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
> index a2ecd7a..6c3ef76 100644
> --- a/gcc/config/aarch64/aarch64.c
> +++ b/gcc/config/aarch64/aarch64.c
> @@ -1480,7 +1480,8 @@ aarch64_load_symref_appropriately (rtx dest, rtx imm,
> 	  tp = gen_lowpart (mode, tp);
> 
> 	emit_insn (gen_rtx_SET (dest, gen_rtx_PLUS (mode, tp, x0)));
> -	set_unique_reg_note (get_last_insn (), REG_EQUIV, imm);
> +        if (REG_P (dest)) 
> +	  set_unique_reg_note (get_last_insn (), REG_EQUIV, imm);
> 	return;
>       }
> 
> @@ -1514,7 +1515,8 @@ aarch64_load_symref_appropriately (rtx dest, rtx imm,
> 	  }
> 
> 	emit_insn (gen_rtx_SET (dest, gen_rtx_PLUS (mode, tp, tmp_reg)));
> -	set_unique_reg_note (get_last_insn (), REG_EQUIV, imm);
> +        if (REG_P (dest)) 
> +	  set_unique_reg_note (get_last_insn (), REG_EQUIV, imm);
> 	return;
>       }
> 
> @@ -1555,7 +1557,8 @@ aarch64_load_symref_appropriately (rtx dest, rtx imm,
> 	    gcc_unreachable ();
> 	  }
> 
> -	set_unique_reg_note (get_last_insn (), REG_EQUIV, imm);
> +        if (REG_P (dest)) 
> +	  set_unique_reg_note (get_last_insn (), REG_EQUIV, imm);
> 	return;
>       }
> 
> @@ -1584,7 +1587,8 @@ aarch64_load_symref_appropriately (rtx dest, rtx imm,
> 	    emit_insn (gen_tlsie_tiny_sidi (dest, imm, tp));
> 	  }
> 
> -	set_unique_reg_note (get_last_insn (), REG_EQUIV, imm);
> +        if (REG_P (dest))
> +	  set_unique_reg_note (get_last_insn (), REG_EQUIV, imm);
> 	return;
>       }
> 
> diff --git a/gcc/testsuite/gcc.target/aarch64/pr81422.C b/gcc/testsuite/gcc.target/aarch64/pr81422.C
> new file mode 100644
> index 0000000..5bcc948
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/aarch64/pr81422.C
> @@ -0,0 +1,15 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O0" } */
> +
> +struct DArray
> +{
> +    __SIZE_TYPE__ length;
> +    int* ptr;
> +};
> +
> +void foo35(DArray)
> +{
> +    static __thread int x[5];
> +    foo35({5, (int*)&x});
> +}
> +
> -- 
> 1.9.1
>

HI, Richard,

> On Oct 5, 2017, at 9:53 AM, Richard Earnshaw (lists) <Richard.Earnshaw@arm.com> wrote:
> 
> Two minor nits to fix:
> 
> - ChangeLog entries should start with a capital letter (s/check/Check/).
> - Please use hard tabs rather than 8 consecutive spaces (each of your
> new 'if' statements).
> 
> OK with those changes.
> 
> R.

Per your comments, my updated patch is following:

since I don’t have the SVN write permission, if the change is good, could you help me to check them in?

thanks a lot.

Qing

===============

gcc/ChangeLog:

      * config/aarch64/aarch64.c (aarch64_load_symref_appropriately):
      Check whether the dest is REG before adding REG_EQUIV note.

gcc/testsuite/ChangeLog:

      PR target/81422
      * gcc.target/aarch64/pr81422.C: New test.

---
 gcc/config/aarch64/aarch64.c               | 12 ++++++++----
 gcc/testsuite/gcc.target/aarch64/pr81422.C | 15 +++++++++++++++
 2 files changed, 23 insertions(+), 4 deletions(-)
 create mode 100644 gcc/testsuite/gcc.target/aarch64/pr81422.C

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index ee98a1f..181f66a 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -1490,7 +1490,8 @@ aarch64_load_symref_appropriately (rtx dest, rtx imm,
 	  tp = gen_lowpart (mode, tp);
 
 	emit_insn (gen_rtx_SET (dest, gen_rtx_PLUS (mode, tp, x0)));
-	set_unique_reg_note (get_last_insn (), REG_EQUIV, imm);
+	if (REG_P (dest))
+	  set_unique_reg_note (get_last_insn (), REG_EQUIV, imm);
 	return;
       }
 
@@ -1524,7 +1525,8 @@ aarch64_load_symref_appropriately (rtx dest, rtx imm,
 	  }
 
 	emit_insn (gen_rtx_SET (dest, gen_rtx_PLUS (mode, tp, tmp_reg)));
-	set_unique_reg_note (get_last_insn (), REG_EQUIV, imm);
+	if (REG_P (dest))
+	  set_unique_reg_note (get_last_insn (), REG_EQUIV, imm);
 	return;
       }
 
@@ -1565,7 +1567,8 @@ aarch64_load_symref_appropriately (rtx dest, rtx imm,
 	    gcc_unreachable ();
 	  }
 
-	set_unique_reg_note (get_last_insn (), REG_EQUIV, imm);
+	if (REG_P (dest))
+	  set_unique_reg_note (get_last_insn (), REG_EQUIV, imm);
 	return;
       }
 
@@ -1594,7 +1597,8 @@ aarch64_load_symref_appropriately (rtx dest, rtx imm,
 	    emit_insn (gen_tlsie_tiny_sidi (dest, imm, tp));
 	  }
 
-	set_unique_reg_note (get_last_insn (), REG_EQUIV, imm);
+	if (REG_P (dest))
+	  set_unique_reg_note (get_last_insn (), REG_EQUIV, imm);
 	return;
       }
 
diff --git a/gcc/testsuite/gcc.target/aarch64/pr81422.C b/gcc/testsuite/gcc.target/aarch64/pr81422.C
new file mode 100644
index 0000000..5bcc948
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/pr81422.C
@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+/* { dg-options "-O0" } */
+
+struct DArray
+{
+    __SIZE_TYPE__ length;
+    int* ptr;
+};
+
+void foo35(DArray)
+{
+    static __thread int x[5];
+    foo35({5, (int*)&x});
+}
+