From: Jose Fonseca <jfonseca@vmware.com>
Date: Fri, 10 Jun 2016 14:42:55 +0000 (+0100)
Subject: gallivm: Never emit llvm.fmuladd on LLVM 3.3.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=2b4cee05715614acb9dd3823f5665199adcf97c2;p=mesa.git

gallivm: Never emit llvm.fmuladd on LLVM 3.3.

Besides the old JIT bug, it seems the X86 backend on LLVM 3.3 doesn't
handle llvm.fmuladd and instead it fall backs to a C function.  Which in
turn causes a segfault on Windows.

Reviewed-by: Roland Scheidegger <sroland@vmware.com>
---

diff --git a/src/gallium/auxiliary/gallivm/lp_bld_arit.c b/src/gallium/auxiliary/gallivm/lp_bld_arit.c
index 5d6a0335654..114c76665f9 100644
--- a/src/gallium/auxiliary/gallivm/lp_bld_arit.c
+++ b/src/gallium/auxiliary/gallivm/lp_bld_arit.c
@@ -270,6 +270,12 @@ lp_build_fmuladd(LLVMBuilderRef builder,
    LLVMTypeRef type = LLVMTypeOf(a);
    assert(type == LLVMTypeOf(b));
    assert(type == LLVMTypeOf(c));
+   if (HAVE_LLVM < 0x0304) {
+      /* XXX: LLVM 3.3 does not breakdown llvm.fmuladd into mul+add when FMA is
+       * not supported, and instead it falls-back to a C function.
+       */
+      return LLVMBuildFAdd(builder, LLVMBuildFMul(builder, a, b, ""), c, "");
+   }
    char intrinsic[32];
    lp_format_intrinsic(intrinsic, sizeof intrinsic, "llvm.fmuladd", type);
    LLVMValueRef args[] = { a, b, c };
diff --git a/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp b/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp
index 5ffe09c9a1b..23ef3edeae7 100644
--- a/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp
+++ b/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp
@@ -570,7 +570,7 @@ lp_build_create_jit_compiler_for_module(LLVMExecutionEngineRef *OutJIT,
     */
    MAttrs.push_back(util_cpu_caps.has_avx  ? "+avx"  : "-avx");
    MAttrs.push_back(util_cpu_caps.has_f16c ? "+f16c" : "-f16c");
-   if (HAVE_LLVM >= 0x0304 || useMCJIT) {
+   if (HAVE_LLVM >= 0x0304) {
       MAttrs.push_back(util_cpu_caps.has_fma  ? "+fma"  : "-fma");
    } else {
       /*