gallivm: add lp_create_builder with an unsafe_fpmath option

Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>

src/gallium/auxiliary/gallivm/lp_bld_misc.cpp

@@ -733,3 +733,17 @@ lp_is_function(LLVMValueRef v)
 	return llvm::isa<llvm::Function>(llvm::unwrap(v));
 #endif
 }
+
+extern "C" LLVMBuilderRef
+lp_create_builder(LLVMContextRef ctx, bool unsafe_fpmath)
+{
+   LLVMBuilderRef builder = LLVMCreateBuilderInContext(ctx);
+
+   if (unsafe_fpmath) {
+      llvm::FastMathFlags flags;
+      flags.setUnsafeAlgebra();
+      llvm::unwrap(builder)->setFastMathFlags(flags);
+   }
+
+   return builder;
+}

src/gallium/auxiliary/gallivm/lp_bld_misc.h

@@ -82,6 +82,9 @@ lp_get_called_value(LLVMValueRef call);
 extern bool
 lp_is_function(LLVMValueRef v);
 
+extern LLVMBuilderRef
+lp_create_builder(LLVMContextRef ctx, bool unsafe_fpmath);
+
 #ifdef __cplusplus
 }
 #endif