i#2267: Expect floatpc failure on AMD processor

Adds CMake detection of the processor vendor.

Relaxes the floatpc_xl8all test to expect failure when running on AMD
for inter-block cases, where DR won't be able to translate as the
processor does not supply the PC if there wasn't an exception.

Issue: #2267

CMakeLists.txt

@@ -320,6 +320,13 @@ if (NOT "${TARGET_ARCH}" STREQUAL "${CMAKE_SYSTEM_PROCESSOR}")
   endif ()
 endif ()
 
+get_processor_vendor(CPU_VENDOR)
+if ("${CPU_VENDOR}" STREQUAL "GenuineIntel")
+  set(CPU_INTEL ON)
+elseif ("${CPU_VENDOR}" STREQUAL "AuthenticAMD")
+  set(CPU_AMD ON)
+endif ()
+
 # Support for running cross-compiled tests under emulation.
 if (CMAKE_CROSSCOMPILING AND DEFINED CMAKE_FIND_ROOT_PATH)
   find_program(QEMU_BINARY qemu-${CMAKE_SYSTEM_PROCESSOR} DOC "QEMU emulation tool")

core/arch/x86/mangle.c

@@ -2322,6 +2322,13 @@ void
 mangle_float_pc(dcontext_t *dcontext, instrlist_t *ilist, instr_t *instr,
                 instr_t *next_instr, uint *flags INOUT)
 {
+    /* XXX i#2267: AMD processors don't provide the last PC when there was no
+     * exception.  Recent processors seem to zero it out.  Should we do the same,
+     * and not supply it for intra-block cases?  For now we do supply it, and
+     * we try (but fail) for inter-block for -translate_fpu_pc (we expect failure
+     * in our floatpc_xl8all test template for AMD).
+     */
+
     /* If there is a prior non-control float instr, we can inline the pc update.
      * Otherwise, we go back to d_r_dispatch.  In the latter case we do not support
      * building traces across the float pc save: we assume it's rare.

make/utils.cmake

@@ -342,3 +342,28 @@ function (check_sve_processor_and_compiler_support out)
   endif ()
   set(${out} ${proc_found_sve} PARENT_SCOPE)
 endfunction (check_sve_processor_and_compiler_support)
+
+function (get_processor_vendor out)
+  set(vendor "<unknown>")
+  if (APPLE)
+    find_program(SYSCTL NAMES sysctl PATHS /usr/sbin)
+    if (SYSCTL)
+      execute_process(COMMAND ${SYSCTL} -n machdep.cpu.vendor
+        OUTPUT_VARIABLE vendor OUTPUT_STRIP_TRAILING_WHITESPACE ERROR_VARIABLE err)
+      if ("${vendor}" STREQUAL "")
+        execute_process(COMMAND ${SYSCTL} -n machdep.cpu.brand_string
+          OUTPUT_VARIABLE vendor OUTPUT_STRIP_TRAILING_WHITESPACE ERROR_VARIABLE err)
+      endif ()
+    endif ()
+  elseif (WIN32)
+    get_filename_component(vendor
+      "[HKEY_LOCAL_MACHINE\\Hardware\\Description\\System\\CentralProcessor\\0;VendorIdentifier]"
+      NAME CACHE)
+  elseif (EXISTS "/proc/cpuinfo")
+    file(READ "/proc/cpuinfo" contents)
+    string(REGEX REPLACE ".*vendor_id[ \t]*:[ \t]+([a-zA-Z0-9_-]+).*" "\\1"
+      vendor "${contents}")
+  endif ()
+  message(STATUS "Processor vendor is ${vendor}")
+  set(${out} ${vendor} PARENT_SCOPE)
+endfunction ()

suite/tests/CMakeLists.txt

@@ -1050,6 +1050,11 @@ function(template2expect outexpect template runops key)
   elseif (DEFINED ${key}_runsve)
     set(rundefs "${rundefs} -D__ARM_FEATURE_SVE")
   endif ()
+  if (CPU_AMD)
+    set(rundefs "${rundefs} -DCPU_AMD")
+  elseif (CPU_INTEL)
+    set(rundefs "${rundefs} -DCPU_INTEL")
+  endif ()
 
   if (DEFINED ${key}_test_sample_client)
     set(rundefs "${rundefs} -DTEST_SAMPLE_CLIENT")

suite/tests/common/floatpc.c

@@ -1,5 +1,5 @@
 /* **********************************************************
- * Copyright (c) 2013 Google, Inc.  All rights reserved.
+ * Copyright (c) 2013-2023 Google, Inc.  All rights reserved.
  * **********************************************************/
 
 /*

suite/tests/common/floatpc.template

@@ -1,6 +1,6 @@
 #ifdef X64
 FXSAVE64 intra is correctly handled
-# if defined(translate_fpu_pc) || defined(hotp_only)
+# if (defined(translate_fpu_pc) || defined(hotp_only)) && !defined(CPU_AMD)
 FXSAVE64 inter is correctly handled
 # else
 FXSAVE64 inter is **incorrectly** handled
@@ -14,7 +14,7 @@ FNSTENV inter is **incorrectly** handled
 # endif
 #endif
 FXSAVE intra is correctly handled
-#if defined(translate_fpu_pc) || defined(hotp_only)
+# if (defined(translate_fpu_pc) || defined(hotp_only)) && !defined(CPU_AMD)
 FXSAVE inter is correctly handled
 #else
 FXSAVE inter is **incorrectly** handled