[Mesa-dev] [PATCH 1/3] gallivm: add create_builder_at_entry helper function

[Nicolai Hähnle]

From: Nicolai Hähnle <nicolai.haehnle at amd.com>

Reduces code duplication.
---
 src/gallium/auxiliary/gallivm/lp_bld_flow.c | 45 ++++++++++++++---------------
 1 file changed, 22 insertions(+), 23 deletions(-)

diff --git a/src/gallium/auxiliary/gallivm/lp_bld_flow.c b/src/gallium/auxiliary/gallivm/lp_bld_flow.c
index f3b3eab..9183f45 100644
--- a/src/gallium/auxiliary/gallivm/lp_bld_flow.c
+++ b/src/gallium/auxiliary/gallivm/lp_bld_flow.c
@@ -447,20 +447,40 @@ lp_build_endif(struct lp_build_if_state *ifthen)
       /* no else clause */
       LLVMBuildCondBr(builder, ifthen->condition,
                       ifthen->true_block, ifthen->merge_block);
    }
 
    /* Resume building code at end of the ifthen->merge_block */
    LLVMPositionBuilderAtEnd(builder, ifthen->merge_block);
 }
 
 
+static LLVMBuilderRef
+create_builder_at_entry(struct gallivm_state *gallivm)
+{
+   LLVMBuilderRef builder = gallivm->builder;
+   LLVMBasicBlockRef current_block = LLVMGetInsertBlock(builder);
+   LLVMValueRef function = LLVMGetBasicBlockParent(current_block);
+   LLVMBasicBlockRef first_block = LLVMGetEntryBasicBlock(function);
+   LLVMValueRef first_instr = LLVMGetFirstInstruction(first_block);
+   LLVMBuilderRef first_builder = LLVMCreateBuilderInContext(gallivm->context);
+
+   if (first_instr) {
+      LLVMPositionBuilderBefore(first_builder, first_instr);
+   } else {
+      LLVMPositionBuilderAtEnd(first_builder, first_block);
+   }
+
+   return first_builder;
+}
+
+
 /**
  * Allocate a scalar (or vector) variable.
  *
  * Although not strictly part of control flow, control flow has deep impact in
  * how variables should be allocated.
  *
  * The mem2reg optimization pass is the recommended way to dealing with mutable
  * variables, and SSA. It looks for allocas and if it can handle them, it
  * promotes them, but only looks for alloca instructions in the entry block of
  * the function. Being in the entry block guarantees that the alloca is only
@@ -468,33 +488,23 @@ lp_build_endif(struct lp_build_if_state *ifthen)
  *
  * See also:
  * - http://www.llvm.org/docs/tutorial/OCamlLangImpl7.html#memory
  */
 LLVMValueRef
 lp_build_alloca(struct gallivm_state *gallivm,
                 LLVMTypeRef type,
                 const char *name)
 {
    LLVMBuilderRef builder = gallivm->builder;
-   LLVMBasicBlockRef current_block = LLVMGetInsertBlock(builder);
-   LLVMValueRef function = LLVMGetBasicBlockParent(current_block);
-   LLVMBasicBlockRef first_block = LLVMGetEntryBasicBlock(function);
-   LLVMValueRef first_instr = LLVMGetFirstInstruction(first_block);
-   LLVMBuilderRef first_builder = LLVMCreateBuilderInContext(gallivm->context);
+   LLVMBuilderRef first_builder = create_builder_at_entry(gallivm);
    LLVMValueRef res;
 
-   if (first_instr) {
-      LLVMPositionBuilderBefore(first_builder, first_instr);
-   } else {
-      LLVMPositionBuilderAtEnd(first_builder, first_block);
-   }
-
    res = LLVMBuildAlloca(first_builder, type, name);
    LLVMBuildStore(builder, LLVMConstNull(type), res);
 
    LLVMDisposeBuilder(first_builder);
 
    return res;
 }
 
 
 /**
@@ -510,30 +520,19 @@ lp_build_alloca(struct gallivm_state *gallivm,
  *
  * See also:
  * - http://www.llvm.org/docs/tutorial/OCamlLangImpl7.html#memory
  */
 LLVMValueRef
 lp_build_array_alloca(struct gallivm_state *gallivm,
                       LLVMTypeRef type,
                       LLVMValueRef count,
                       const char *name)
 {
-   LLVMBuilderRef builder = gallivm->builder;
-   LLVMBasicBlockRef current_block = LLVMGetInsertBlock(builder);
-   LLVMValueRef function = LLVMGetBasicBlockParent(current_block);
-   LLVMBasicBlockRef first_block = LLVMGetEntryBasicBlock(function);
-   LLVMValueRef first_instr = LLVMGetFirstInstruction(first_block);
-   LLVMBuilderRef first_builder = LLVMCreateBuilderInContext(gallivm->context);
+   LLVMBuilderRef first_builder = create_builder_at_entry(gallivm);
    LLVMValueRef res;
 
-   if (first_instr) {
-      LLVMPositionBuilderBefore(first_builder, first_instr);
-   } else {
-      LLVMPositionBuilderAtEnd(first_builder, first_block);
-   }
-
    res = LLVMBuildArrayAlloca(first_builder, type, count, name);
 
    LLVMDisposeBuilder(first_builder);
 
    return res;
 }
-- 
2.7.4