gcc/0071-Don-t-assume-it-s-AVX_U128_CLEAN-after-call_insn-who.patch

From 204ffa7f503411ccac0161c951726274648b6374 Mon Sep 17 00:00:00 2001
From: liuhongt <hongtao.liu@intel.com>
Date: Thu, 7 Dec 2023 09:17:27 +0800
Subject: [PATCH 16/32] Don't assume it's AVX_U128_CLEAN after call_insn whose
 abi.mode_clobber(V4DImode) deosn't contains all SSE_REGS.

If the function desn't clobber any sse registers or only clobber
128-bit part, then vzeroupper isn't issued before the function exit.
the status not CLEAN but ANY after the function.

Also for sibling_call, it's safe to issue an vzeroupper. Also there
could be missing vzeroupper since there's no mode_exit for
sibling_call_p.

gcc/ChangeLog:

	PR target/112891
	* config/i386/i386.cc (ix86_avx_u128_mode_after): Return
	AVX_U128_ANY if callee_abi doesn't clobber all_sse_regs to
	align with ix86_avx_u128_mode_needed.
	(ix86_avx_u128_mode_needed): Return AVX_U128_ClEAN for
	sibling_call.

gcc/testsuite/ChangeLog:

	* gcc.target/i386/pr112891.c: New test.
	* gcc.target/i386/pr112891-2.c: New test.

(cherry picked from commit fc189a08f5b7ad5889bd4c6b320c1dd99dd5d642)
---
 gcc/config/i386/i386.cc                    | 22 +++++++++++++---
 gcc/testsuite/gcc.target/i386/pr112891-2.c | 30 ++++++++++++++++++++++
 gcc/testsuite/gcc.target/i386/pr112891.c   | 29 +++++++++++++++++++++
 3 files changed, 78 insertions(+), 3 deletions(-)
 create mode 100644 gcc/testsuite/gcc.target/i386/pr112891-2.c
 create mode 100644 gcc/testsuite/gcc.target/i386/pr112891.c

diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
index e75d37023..60f3296b0 100644
--- a/gcc/config/i386/i386.cc
+++ b/gcc/config/i386/i386.cc
@@ -14416,8 +14416,12 @@ ix86_avx_u128_mode_needed (rtx_insn *insn)
 	 modes wider than 256 bits.  It's only safe to issue a
 	 vzeroupper if all SSE registers are clobbered.  */
       const function_abi &abi = insn_callee_abi (insn);
-      if (!hard_reg_set_subset_p (reg_class_contents[SSE_REGS],
-				  abi.mode_clobbers (V4DImode)))
+      /* Should be safe to issue an vzeroupper before sibling_call_p.
+	 Also there not mode_exit for sibling_call, so there could be
+	 missing vzeroupper for that.  */
+      if (!(SIBLING_CALL_P (insn)
+	    || hard_reg_set_subset_p (reg_class_contents[SSE_REGS],
+				      abi.mode_clobbers (V4DImode))))
 	return AVX_U128_ANY;
 
       return AVX_U128_CLEAN;
@@ -14555,7 +14559,19 @@ ix86_avx_u128_mode_after (int mode, rtx_insn *insn)
       bool avx_upper_reg_found = false;
       note_stores (insn, ix86_check_avx_upper_stores, &avx_upper_reg_found);
 
-      return avx_upper_reg_found ? AVX_U128_DIRTY : AVX_U128_CLEAN;
+      if (avx_upper_reg_found)
+	return AVX_U128_DIRTY;
+
+      /* If the function desn't clobber any sse registers or only clobber
+	 128-bit part, Then vzeroupper isn't issued before the function exit.
+	 the status not CLEAN but ANY after the function.  */
+      const function_abi &abi = insn_callee_abi (insn);
+      if (!(SIBLING_CALL_P (insn)
+	    || hard_reg_set_subset_p (reg_class_contents[SSE_REGS],
+				      abi.mode_clobbers (V4DImode))))
+	return AVX_U128_ANY;
+
+      return  AVX_U128_CLEAN;
     }
 
   /* Otherwise, return current mode.  Remember that if insn
diff --git a/gcc/testsuite/gcc.target/i386/pr112891-2.c b/gcc/testsuite/gcc.target/i386/pr112891-2.c
new file mode 100644
index 000000000..164c3985d
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr112891-2.c
@@ -0,0 +1,30 @@
+/* { dg-do compile } */
+/* { dg-options "-mavx2 -O3" } */
+/* { dg-final { scan-assembler-times "vzeroupper" 1 } } */
+
+void
+__attribute__((noinline))
+bar (double* a)
+{
+  a[0] = 1.0;
+  a[1] = 2.0;
+}
+
+double
+__attribute__((noinline))
+foo (double* __restrict a, double* b)
+{
+  a[0] += b[0];
+  a[1] += b[1];
+  a[2] += b[2];
+  a[3] += b[3];
+  bar (b);
+  return a[5] + b[5];
+}
+
+double
+foo1 (double* __restrict a, double* b)
+{
+  double c = foo (a, b);
+  return __builtin_exp (c);
+}
diff --git a/gcc/testsuite/gcc.target/i386/pr112891.c b/gcc/testsuite/gcc.target/i386/pr112891.c
new file mode 100644
index 000000000..dbf6c6794
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr112891.c
@@ -0,0 +1,29 @@
+/* { dg-do compile } */
+/* { dg-options "-mavx2 -O3" } */
+/* { dg-final { scan-assembler-times "vzeroupper" 1 } } */
+
+void
+__attribute__((noinline))
+bar (double* a)
+{
+  a[0] = 1.0;
+  a[1] = 2.0;
+}
+
+void
+__attribute__((noinline))
+foo (double* __restrict a, double* b)
+{
+  a[0] += b[0];
+  a[1] += b[1];
+  a[2] += b[2];
+  a[3] += b[3];
+  bar (b);
+}
+
+double
+foo1 (double* __restrict a, double* b)
+{
+  foo (a, b);
+  return __builtin_exp (b[1]);
+}
-- 
2.28.0.windows.1