[gcc r11-8754] x86: Don't enable UINTR in 32-bit mode

[gcc r11-8754] x86: Don't enable UINTR in 32-bit mode

[H.J. Lu]

https://gcc.gnu.org/g:a0128f11e9dadc3cc3ed0ad0edb36593b16f72e8

commit r11-8754-ga0128f11e9dadc3cc3ed0ad0edb36593b16f72e8
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Fri Jul 9 09:16:01 2021 -0700

    x86: Don't enable UINTR in 32-bit mode
    
    UINTR is available only in 64-bit mode.  Since the codegen target is
    unknown when the the gcc driver is processing -march=native, to properly
    handle UINTR for -march=native:
    
    1. Pass "arch [32|64]" and "tune [32|64]" to host_detect_local_cpu to
    indicate 32-bit and 64-bit codegen.
    2. Change ix86_option_override_internal to enable UINTR only in 64-bit
    mode for -march=CPU when PTA_CPU includes PTA_UINTR.
    
    gcc/
    
            PR target/101395
            * config/i386/driver-i386.c (host_detect_local_cpu): Check
            "arch [32|64]" and "tune [32|64]" for 32-bit and 64-bit codegen.
            Enable UINTR only for 64-bit codegen.
            * config/i386/i386-options.c
            (ix86_option_override_internal::DEF_PTA): Skip PTA_UINTR if not
            in 64-bit mode.
            * config/i386/i386.h (ARCH_ARG): New.
            (CC1_CPU_SPEC): Pass "[arch|tune] 32" for 32-bit codegen and
            "[arch|tune] 64" for 64-bit codegen.
    
    gcc/testsuite/
    
            PR target/101395
            * gcc.target/i386/pr101395-1.c: New test.
            * gcc.target/i386/pr101395-2.c: Likewise.
            * gcc.target/i386/pr101395-3.c: Likewise.
    
    (cherry picked from commit cc11b924bfe7752edbba052ca71653f46a60887a)

Diff:
---
 gcc/config/i386/driver-i386.c              | 25 +++++++++++++++++++------
 gcc/config/i386/i386-options.c             |  3 ++-
 gcc/config/i386/i386.h                     |  7 ++++---
 gcc/testsuite/gcc.target/i386/pr101395-1.c | 12 ++++++++++++
 gcc/testsuite/gcc.target/i386/pr101395-2.c | 22 ++++++++++++++++++++++
 gcc/testsuite/gcc.target/i386/pr101395-3.c |  6 ++++++
 6 files changed, 65 insertions(+), 10 deletions(-)

diff --git a/gcc/config/i386/driver-i386.c b/gcc/config/i386/driver-i386.c
index dd9236616b4..f844a168ddb 100644
--- a/gcc/config/i386/driver-i386.c
+++ b/gcc/config/i386/driver-i386.c
@@ -370,9 +370,9 @@ detect_caches_intel (bool xeon_mp, unsigned max_level,
 }
 
 /* This will be called by the spec parser in gcc.c when it sees
-   a %:local_cpu_detect(args) construct.  Currently it will be called
-   with either "arch" or "tune" as argument depending on if -march=native
-   or -mtune=native is to be substituted.
+   a %:local_cpu_detect(args) construct.  Currently it will be
+   called with either "arch [32|64]" or "tune [32|64]" as argument
+   depending on if -march=native or -mtune=native is to be substituted.
 
    It returns a string containing new command line parameters to be
    put at the place of the above two options, depending on what CPU
@@ -401,7 +401,7 @@ const char *host_detect_local_cpu (int argc, const char **argv)
 
   unsigned int l2sizekb = 0;
 
-  if (argc < 1)
+  if (argc < 2)
     return NULL;
 
   arch = !strcmp (argv[0], "arch");
@@ -409,6 +409,15 @@ const char *host_detect_local_cpu (int argc, const char **argv)
   if (!arch && strcmp (argv[0], "tune"))
     return NULL;
 
+  bool codegen_x86_64;
+
+  if (!strcmp (argv[1], "32"))
+    codegen_x86_64 = false;
+  else if (!strcmp (argv[1], "64"))
+    codegen_x86_64 = true;
+  else
+    return NULL;
+
   struct __processor_model cpu_model = { };
   struct __processor_model2 cpu_model2 = { };
   unsigned int cpu_features2[SIZE_OF_CPU_FEATURES] = { };
@@ -804,8 +813,12 @@ const char *host_detect_local_cpu (int argc, const char **argv)
 	if (isa_names_table[i].option)
 	  {
 	    if (has_feature (isa_names_table[i].feature))
-	      options = concat (options, " ",
-				isa_names_table[i].option, NULL);
+	      {
+		if (codegen_x86_64
+		    || isa_names_table[i].feature != FEATURE_UINTR)
+		  options = concat (options, " ",
+				    isa_names_table[i].option, NULL);
+	      }
 	    else
 	      options = concat (options, neg_option,
 				isa_names_table[i].option + 2, NULL);
diff --git a/gcc/config/i386/i386-options.c b/gcc/config/i386/i386-options.c
index a58968790a3..18d2c0b9f99 100644
--- a/gcc/config/i386/i386-options.c
+++ b/gcc/config/i386/i386-options.c
@@ -2368,7 +2368,8 @@ ix86_option_override_internal (bool main_args_p,
 	if (((processor_alias_table[i].flags & PTA_PKU) != 0)
 	    && !(opts->x_ix86_isa_flags_explicit & OPTION_MASK_ISA_PKU))
 	  opts->x_ix86_isa_flags |= OPTION_MASK_ISA_PKU;
-	if (((processor_alias_table[i].flags & PTA_UINTR) != 0)
+	if (TARGET_64BIT
+	    && ((processor_alias_table[i].flags & PTA_UINTR) != 0)
 	    && !(opts->x_ix86_isa_flags2_explicit & OPTION_MASK_ISA2_UINTR))
 	  opts->x_ix86_isa_flags2 |= OPTION_MASK_ISA2_UINTR;
 	if (((processor_alias_table[i].flags & PTA_HRESET) != 0)
diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
index 97700d797a7..1dd467920e7 100644
--- a/gcc/config/i386/i386.h
+++ b/gcc/config/i386/i386.h
@@ -789,10 +789,11 @@ extern const char *host_detect_local_cpu (int argc, const char **argv);
 #ifndef HAVE_LOCAL_CPU_DETECT
 #define CC1_CPU_SPEC CC1_CPU_SPEC_1
 #else
+#define ARCH_ARG "%{" OPT_ARCH64 ":64;:32}"
 #define CC1_CPU_SPEC CC1_CPU_SPEC_1 \
-"%{march=native:%>march=native %:local_cpu_detect(arch) \
-  %{!mtune=*:%>mtune=native %:local_cpu_detect(tune)}} \
-%{mtune=native:%>mtune=native %:local_cpu_detect(tune)}"
+"%{march=native:%>march=native %:local_cpu_detect(arch " ARCH_ARG ") \
+  %{!mtune=*:%>mtune=native %:local_cpu_detect(tune " ARCH_ARG ")}} \
+%{mtune=native:%>mtune=native %:local_cpu_detect(tune " ARCH_ARG ")}"
 #endif
 #endif
 \f
diff --git a/gcc/testsuite/gcc.target/i386/pr101395-1.c b/gcc/testsuite/gcc.target/i386/pr101395-1.c
new file mode 100644
index 00000000000..74c8bfe891a
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr101395-1.c
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -march=sapphirerapids" } */
+
+#ifdef __x86_64__
+# ifndef __UINTR__
+#  error UINTR is not enabled for Sapphirerapids
+# endif
+#else
+# ifdef __UINTR__
+#  error UINTR is not usable in 32-bit mode
+# endif
+#endif
diff --git a/gcc/testsuite/gcc.target/i386/pr101395-2.c b/gcc/testsuite/gcc.target/i386/pr101395-2.c
new file mode 100644
index 00000000000..f2b677f8c80
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr101395-2.c
@@ -0,0 +1,22 @@
+/* { dg-do run } */
+/* { dg-options "-O2 -march=native" } */
+
+int
+main ()
+{
+  if (__builtin_cpu_supports ("uintr"))
+    {
+#ifdef __x86_64__
+# ifndef __UINTR__
+      __builtin_abort ();
+# endif
+#else
+# ifdef __UINTR__
+      __builtin_abort ();
+# endif
+#endif
+      return 0;
+    }
+
+  return 0;
+}
diff --git a/gcc/testsuite/gcc.target/i386/pr101395-3.c b/gcc/testsuite/gcc.target/i386/pr101395-3.c
new file mode 100644
index 00000000000..bc6ab423c93
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr101395-3.c
@@ -0,0 +1,6 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -march=native -mno-uintr" } */
+
+#ifdef __UINTR__
+# error UINTR should be disabled
+#endif