From f7a4c2dbb35831f8525e1f029dbf73979963af09 Mon Sep 17 00:00:00 2001
From: Andreas Beckmann <anbe@debian.org>
Date: Thu, 7 Apr 2022 12:04:05 +0200
Subject: [PATCH] [PATCH 37/42] add pocl_get_distro_cpu_name()

in distro builds, map each kernellib_name to a specific llvm_cpu
which is then used as compilation target instead of the native cpu

this limits the possible code generation targets in distro builds
in order to be able to run tests against all of them with a minimal
number of different (physical) CPU models

Gbp-Pq: Name 0037-add-pocl_get_distro_cpu_name.patch
---
 lib/CL/pocl_llvm.h        |  4 ++++
 lib/CL/pocl_llvm_utils.cc | 36 ++++++++++++++++++++++++++++++++++--
 2 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/lib/CL/pocl_llvm.h b/lib/CL/pocl_llvm.h
index 5ed4130..30dc357 100644
--- a/lib/CL/pocl_llvm.h
+++ b/lib/CL/pocl_llvm.h
@@ -43,6 +43,10 @@ extern "C" {
   POCL_EXPORT
   const char *pocl_get_distro_kernellib_name ();
 
+  /* For distro builds, return the target cpu name for a kernellib name */
+  POCL_EXPORT
+  const char *pocl_get_distro_cpu_name (const char *kernellib_name);
+
   /* Returns if the cpu supports FMA instruction (uses LLVM). */
   int cpu_has_fma ();
 
diff --git a/lib/CL/pocl_llvm_utils.cc b/lib/CL/pocl_llvm_utils.cc
index c55ee07..dca2ad6 100644
--- a/lib/CL/pocl_llvm_utils.cc
+++ b/lib/CL/pocl_llvm_utils.cc
@@ -160,29 +160,39 @@ char *pocl_get_llvm_cpu_name() {
 #ifdef KERNELLIB_HOST_DISTRO_VARIANTS
 const struct kernellib_features {
   const char *kernellib_name;
+  const char *cpu_name;
   const char *features[12];
 } kernellib_feature_map[] = {
 // order the entries s.t. if a cpu matches multiple entries, the "best" match
 // comes last
 #if defined(__x86_64__)
     "sse2",
+    "athlon64",
     {"sse2", NULL},
     "ssse3",
+    "core2",
     {"sse2", "ssse3", "cx16", NULL},
     "sse41",
+    "penryn",
     {"sse2", "sse4.1", "cx16", NULL},
     "avx",
+    "sandybridge",
     {"sse2", "avx", "cx16", "popcnt", NULL},
     "avx_f16c",
+    "ivybridge",
     {"sse2", "avx", "cx16", "popcnt", "f16c", NULL},
     "avx_fma4",
+    "bdver1",
     {"sse2", "avx", "cx16", "popcnt", "xop", "fma4", NULL},
     "avx2",
+    "haswell",
     {"sse2", "avx", "avx2", "cx16", "popcnt", "lzcnt", "f16c", "fma", "bmi",
      "bmi2", NULL},
     "avx512",
+    "skylake-avx512",
     {"sse2", "avx512f", NULL},
 #endif
+    NULL,
     NULL,
     {NULL}};
 
@@ -192,7 +202,7 @@ const char *pocl_get_distro_kernellib_name() {
 
   if (!llvm::sys::getHostCPUFeatures(Features)) {
     POCL_MSG_WARN("LLVM can't get host CPU flags!\n");
-    return "";
+    return NULL;
   }
 
   const kernellib_features *best_match = NULL;
@@ -209,11 +219,33 @@ const char *pocl_get_distro_kernellib_name() {
   if (!best_match) {
     POCL_MSG_WARN("Can't find a kernellib supported by the host CPU (%s)\n",
                   llvm::sys::getHostCPUName());
-    return "";
+    return NULL;
   }
 
   return best_match->kernellib_name;
 }
+
+/* for "distro" style kernel libs, return which target cpu to use for a given
+ * kernellib */
+const char *pocl_get_distro_cpu_name(const char *kernellib_name) {
+  StringMap<bool> Features;
+
+  if (!llvm::sys::getHostCPUFeatures(Features)) {
+    POCL_MSG_WARN("LLVM can't get host CPU flags!\n");
+    return NULL;
+  }
+
+  const kernellib_features *best_match = NULL;
+  for (const kernellib_features *kf = kernellib_feature_map; kf->kernellib_name;
+       ++kf) {
+    if (!strcmp(kernellib_name, kf->kernellib_name))
+      return kf->cpu_name;
+  }
+
+  POCL_MSG_WARN("Can't find a cpu name matching the kernellib (%s)\n",
+                kernellib_name);
+  return NULL;
+}
 #endif
 
 int pocl_bitcode_is_triple(const char *bitcode, size_t size, const char *triple) {
-- 
2.30.2