From: Kito Cheng <kito.cheng@gmail.com>
Date: Tue, 17 Jan 2017 16:56:30 +0000 (+0000)
Subject: re PR target/79079 ([6] Wrong code gen for __builtin_mul_overflow when TRULY_NOOP_TRU... 
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=4ed543bcd40a76ac940bc1759ae53cd3625d9718;p=gcc.git

re PR target/79079 ([6] Wrong code gen for __builtin_mul_overflow when TRULY_NOOP_TRUNCATION (32, 64) == false)

	PR target/79079
	* internal-fn.c (expand_mul_overflow): Use convert_modes instead of
	gen_lowpart.

Co-Authored-By: Kuan-Lin Chen <kuanlinchentw@gmail.com>

From-SVN: r244539
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index cc05d2c9c2c..6530fd1de99 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2017-01-17  Kito Cheng  <kito.cheng@gmail.com>
+            Kuan-Lin Chen  <kuanlinchentw@gmail.com>
+
+	PR target/79079
+	* internal-fn.c (expand_mul_overflow): Use convert_modes instead of
+	gen_lowpart.
+
 2017-01-17  Vladimir Makarov  <vmakarov@redhat.com>
 
 	PR target/79058
diff --git a/gcc/internal-fn.c b/gcc/internal-fn.c
index 7fb44aa08fe..5d71cb2e08d 100644
--- a/gcc/internal-fn.c
+++ b/gcc/internal-fn.c
@@ -1483,8 +1483,8 @@ expand_mul_overflow (location_t loc, tree lhs, tree arg0, tree arg1,
 	  res = expand_expr_real_2 (&ops, NULL_RTX, wmode, EXPAND_NORMAL);
 	  rtx hipart = expand_shift (RSHIFT_EXPR, wmode, res, prec,
 				     NULL_RTX, uns);
-	  hipart = gen_lowpart (mode, hipart);
-	  res = gen_lowpart (mode, res);
+	  hipart = convert_modes (mode, wmode, hipart, uns);
+	  res = convert_modes (mode, wmode, res, uns);
 	  if (uns)
 	    /* For the unsigned multiplication, there was overflow if
 	       HIPART is non-zero.  */
@@ -1517,16 +1517,16 @@ expand_mul_overflow (location_t loc, tree lhs, tree arg0, tree arg1,
 	  unsigned int hprec = GET_MODE_PRECISION (hmode);
 	  rtx hipart0 = expand_shift (RSHIFT_EXPR, mode, op0, hprec,
 				      NULL_RTX, uns);
-	  hipart0 = gen_lowpart (hmode, hipart0);
-	  rtx lopart0 = gen_lowpart (hmode, op0);
+	  hipart0 = convert_modes (hmode, mode, hipart0, uns);
+	  rtx lopart0 = convert_modes (hmode, mode, op0, uns);
 	  rtx signbit0 = const0_rtx;
 	  if (!uns)
 	    signbit0 = expand_shift (RSHIFT_EXPR, hmode, lopart0, hprec - 1,
 				     NULL_RTX, 0);
 	  rtx hipart1 = expand_shift (RSHIFT_EXPR, mode, op1, hprec,
 				      NULL_RTX, uns);
-	  hipart1 = gen_lowpart (hmode, hipart1);
-	  rtx lopart1 = gen_lowpart (hmode, op1);
+	  hipart1 = convert_modes (hmode, mode, hipart1, uns);
+	  rtx lopart1 = convert_modes (hmode, mode, op1, uns);
 	  rtx signbit1 = const0_rtx;
 	  if (!uns)
 	    signbit1 = expand_shift (RSHIFT_EXPR, hmode, lopart1, hprec - 1,
@@ -1717,11 +1717,12 @@ expand_mul_overflow (location_t loc, tree lhs, tree arg0, tree arg1,
 	     if (loxhi >> (bitsize / 2) == 0		 (if uns).  */
 	  rtx hipartloxhi = expand_shift (RSHIFT_EXPR, mode, loxhi, hprec,
 					  NULL_RTX, 0);
-	  hipartloxhi = gen_lowpart (hmode, hipartloxhi);
+	  hipartloxhi = convert_modes (hmode, mode, hipartloxhi, 0);
 	  rtx signbitloxhi = const0_rtx;
 	  if (!uns)
 	    signbitloxhi = expand_shift (RSHIFT_EXPR, hmode,
-					 gen_lowpart (hmode, loxhi),
+					 convert_modes (hmode, mode,
+							loxhi, 0),
 					 hprec - 1, NULL_RTX, 0);
 
 	  do_compare_rtx_and_jump (signbitloxhi, hipartloxhi, NE, true, hmode,
@@ -1731,7 +1732,8 @@ expand_mul_overflow (location_t loc, tree lhs, tree arg0, tree arg1,
 	  /* res = (loxhi << (bitsize / 2)) | (hmode) lo0xlo1;  */
 	  rtx loxhishifted = expand_shift (LSHIFT_EXPR, mode, loxhi, hprec,
 					   NULL_RTX, 1);
-	  tem = convert_modes (mode, hmode, gen_lowpart (hmode, lo0xlo1), 1);
+	  tem = convert_modes (mode, hmode,
+			       convert_modes (hmode, mode, lo0xlo1, 1), 1);
 
 	  tem = expand_simple_binop (mode, IOR, loxhishifted, tem, res,
 				     1, OPTAB_DIRECT);