From: Michael Meissner <2019-02-12  Michael Meissner  meissner@linux.ibm.com>
Date: Thu, 16 Apr 2020 16:49:22 +0000 (-0400)
Subject: Fix target/94557 PowerPC regression on GCC 9 (variable vec_extract)
X-Git-Tag: misc/first-auto-changelog-9~122
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=baf3a5a94244b4a260810825870be6ecc15fa35a;p=thirdparty%2Fgcc.git

Fix target/94557 PowerPC regression on GCC 9 (variable vec_extract)

2020-04-16  Michael Meissner  <meissner@linux.ibm.com>

	PR target/94557
	* config/rs6000/rs6000.c (rs6000_adjust_vec_address): Fix
	regression caused by PR target/93932 backport.  Mask variable
	vector extract index so it does not go beyond the vector when
	extracting a vector element from memory.
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index f90fe0d47180..a7949385573b 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2020-04-16  Michael Meissner  <meissner@linux.ibm.com>
+
+	PR target/94557
+	* config/rs6000/rs6000.c (rs6000_adjust_vec_address): Fix
+	regression caused by PR target/93932 backport.  Mask variable
+	vector extract index so it does not go beyond the vector when
+	extracting a vector element from memory.
+
 2020-04-16  Richard Biener  <rguenther@suse.de>
 
 	Backport from mainline
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 8e63249d4ba9..f7c538c4d54e 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -7047,18 +7047,25 @@ rs6000_adjust_vec_address (rtx scalar_reg,
     element_offset = GEN_INT (INTVAL (element) * scalar_size);
   else
     {
+      /* Mask the element to make sure the element number is between 0 and the
+	 maximum number of elements - 1 so that we don't generate an address
+	 outside the vector.  */
+      rtx num_ele_m1 = GEN_INT (GET_MODE_NUNITS (GET_MODE (mem)) - 1);
+      rtx and_op = gen_rtx_AND (Pmode, element, num_ele_m1);
+      emit_insn (gen_rtx_SET (base_tmp, and_op));
+
       int byte_shift = exact_log2 (scalar_size);
       gcc_assert (byte_shift >= 0);
 
       if (byte_shift == 0)
-	element_offset = element;
+	element_offset = base_tmp;
 
       else
 	{
 	  if (TARGET_POWERPC64)
-	    emit_insn (gen_ashldi3 (base_tmp, element, GEN_INT (byte_shift)));
+	    emit_insn (gen_ashldi3 (base_tmp, base_tmp, GEN_INT (byte_shift)));
 	  else
-	    emit_insn (gen_ashlsi3 (base_tmp, element, GEN_INT (byte_shift)));
+	    emit_insn (gen_ashlsi3 (base_tmp, base_tmp, GEN_INT (byte_shift)));
 
 	  element_offset = base_tmp;
 	}