ac: add if/loop build helpers

These have been ported over from radeonsi.

Reviewed-by: Marek Olšák <marek.olsak@amd.com>

diff --git a/src/amd/common/ac_llvm_build.c b/src/amd/common/ac_llvm_build.c
index da2213d40baa0aa0beb477151e8f604129361b77..9851cafb7fd9504645369328a63e51813c53f430 100644 (file)
--- a/src/amd/common/ac_llvm_build.c
+++ b/src/amd/common/ac_llvm_build.c
@@ -41,6 +41,16 @@
 
 #include "shader_enums.h"
 
+#define AC_LLVM_INITIAL_CF_DEPTH 4
+
+/* Data for if/else/endif and bgnloop/endloop control flow structures.
+ */
+struct ac_llvm_flow {
+       /* Loop exit or next part of if/else/endif. */
+       LLVMBasicBlockRef next_block;
+       LLVMBasicBlockRef loop_entry_block;
+};
+
 /* Initialize module-independent parts of the context.
  *
  * The caller is responsible for initializing ctx::module and ctx::builder.
@@ -105,6 +115,14 @@ ac_llvm_context_init(struct ac_llvm_context *ctx, LLVMContextRef context,
        ctx->empty_md = LLVMMDNodeInContext(ctx->context, NULL, 0);
 }
 
+void
+ac_llvm_context_dispose(struct ac_llvm_context *ctx)
+{
+       free(ctx->flow);
+       ctx->flow = NULL;
+       ctx->flow_depth_max = 0;
+}
+
 int
 ac_get_llvm_num_components(LLVMValueRef value)
 {
@@ -2146,3 +2164,174 @@ LLVMTypeRef ac_array_in_const32_addr_space(LLVMTypeRef elem_type)
        return LLVMPointerType(LLVMArrayType(elem_type, 0),
                               AC_CONST_32BIT_ADDR_SPACE);
 }
+
+static struct ac_llvm_flow *
+get_current_flow(struct ac_llvm_context *ctx)
+{
+       if (ctx->flow_depth > 0)
+               return &ctx->flow[ctx->flow_depth - 1];
+       return NULL;
+}
+
+static struct ac_llvm_flow *
+get_innermost_loop(struct ac_llvm_context *ctx)
+{
+       for (unsigned i = ctx->flow_depth; i > 0; --i) {
+               if (ctx->flow[i - 1].loop_entry_block)
+                       return &ctx->flow[i - 1];
+       }
+       return NULL;
+}
+
+static struct ac_llvm_flow *
+push_flow(struct ac_llvm_context *ctx)
+{
+       struct ac_llvm_flow *flow;
+
+       if (ctx->flow_depth >= ctx->flow_depth_max) {
+               unsigned new_max = MAX2(ctx->flow_depth << 1,
+                                       AC_LLVM_INITIAL_CF_DEPTH);
+
+               ctx->flow = realloc(ctx->flow, new_max * sizeof(*ctx->flow));
+               ctx->flow_depth_max = new_max;
+       }
+
+       flow = &ctx->flow[ctx->flow_depth];
+       ctx->flow_depth++;
+
+       flow->next_block = NULL;
+       flow->loop_entry_block = NULL;
+       return flow;
+}
+
+static void set_basicblock_name(LLVMBasicBlockRef bb, const char *base,
+                               int label_id)
+{
+       char buf[32];
+       snprintf(buf, sizeof(buf), "%s%d", base, label_id);
+       LLVMSetValueName(LLVMBasicBlockAsValue(bb), buf);
+}
+
+/* Append a basic block at the level of the parent flow.
+ */
+static LLVMBasicBlockRef append_basic_block(struct ac_llvm_context *ctx,
+                                           const char *name)
+{
+       assert(ctx->flow_depth >= 1);
+
+       if (ctx->flow_depth >= 2) {
+               struct ac_llvm_flow *flow = &ctx->flow[ctx->flow_depth - 2];
+
+               return LLVMInsertBasicBlockInContext(ctx->context,
+                                                    flow->next_block, name);
+       }
+
+       LLVMValueRef main_fn =
+               LLVMGetBasicBlockParent(LLVMGetInsertBlock(ctx->builder));
+       return LLVMAppendBasicBlockInContext(ctx->context, main_fn, name);
+}
+
+/* Emit a branch to the given default target for the current block if
+ * applicable -- that is, if the current block does not already contain a
+ * branch from a break or continue.
+ */
+static void emit_default_branch(LLVMBuilderRef builder,
+                               LLVMBasicBlockRef target)
+{
+       if (!LLVMGetBasicBlockTerminator(LLVMGetInsertBlock(builder)))
+                LLVMBuildBr(builder, target);
+}
+
+void ac_build_bgnloop(struct ac_llvm_context *ctx, int label_id)
+{
+       struct ac_llvm_flow *flow = push_flow(ctx);
+       flow->loop_entry_block = append_basic_block(ctx, "LOOP");
+       flow->next_block = append_basic_block(ctx, "ENDLOOP");
+       set_basicblock_name(flow->loop_entry_block, "loop", label_id);
+       LLVMBuildBr(ctx->builder, flow->loop_entry_block);
+       LLVMPositionBuilderAtEnd(ctx->builder, flow->loop_entry_block);
+}
+
+void ac_build_break(struct ac_llvm_context *ctx)
+{
+       struct ac_llvm_flow *flow = get_innermost_loop(ctx);
+       LLVMBuildBr(ctx->builder, flow->next_block);
+}
+
+void ac_build_continue(struct ac_llvm_context *ctx)
+{
+       struct ac_llvm_flow *flow = get_innermost_loop(ctx);
+       LLVMBuildBr(ctx->builder, flow->loop_entry_block);
+}
+
+void ac_build_else(struct ac_llvm_context *ctx, int label_id)
+{
+       struct ac_llvm_flow *current_branch = get_current_flow(ctx);
+       LLVMBasicBlockRef endif_block;
+
+       assert(!current_branch->loop_entry_block);
+
+       endif_block = append_basic_block(ctx, "ENDIF");
+       emit_default_branch(ctx->builder, endif_block);
+
+       LLVMPositionBuilderAtEnd(ctx->builder, current_branch->next_block);
+       set_basicblock_name(current_branch->next_block, "else", label_id);
+
+       current_branch->next_block = endif_block;
+}
+
+void ac_build_endif(struct ac_llvm_context *ctx, int label_id)
+{
+       struct ac_llvm_flow *current_branch = get_current_flow(ctx);
+
+       assert(!current_branch->loop_entry_block);
+
+       emit_default_branch(ctx->builder, current_branch->next_block);
+       LLVMPositionBuilderAtEnd(ctx->builder, current_branch->next_block);
+       set_basicblock_name(current_branch->next_block, "endif", label_id);
+
+       ctx->flow_depth--;
+}
+
+void ac_build_endloop(struct ac_llvm_context *ctx, int label_id)
+{
+       struct ac_llvm_flow *current_loop = get_current_flow(ctx);
+
+       assert(current_loop->loop_entry_block);
+
+       emit_default_branch(ctx->builder, current_loop->loop_entry_block);
+
+       LLVMPositionBuilderAtEnd(ctx->builder, current_loop->next_block);
+       set_basicblock_name(current_loop->next_block, "endloop", label_id);
+       ctx->flow_depth--;
+}
+
+static void if_cond_emit(struct ac_llvm_context *ctx, LLVMValueRef cond,
+                        int label_id)
+{
+       struct ac_llvm_flow *flow = push_flow(ctx);
+       LLVMBasicBlockRef if_block;
+
+       if_block = append_basic_block(ctx, "IF");
+       flow->next_block = append_basic_block(ctx, "ELSE");
+       set_basicblock_name(if_block, "if", label_id);
+       LLVMBuildCondBr(ctx->builder, cond, if_block, flow->next_block);
+       LLVMPositionBuilderAtEnd(ctx->builder, if_block);
+}
+
+void ac_build_if(struct ac_llvm_context *ctx, LLVMValueRef value,
+                int label_id)
+{
+       LLVMValueRef cond = LLVMBuildFCmp(ctx->builder, LLVMRealUNE,
+                                         value, ctx->f32_0, "");
+       if_cond_emit(ctx, cond, label_id);
+}
+
+void ac_build_uif(struct ac_llvm_context *ctx, LLVMValueRef value,
+                 int label_id)
+{
+       LLVMValueRef cond = LLVMBuildICmp(ctx->builder, LLVMIntNE,
+                                         ac_to_integer(ctx, value),
+                                         ctx->i32_0, "");
+       if_cond_emit(ctx, cond, label_id);
+}

diff --git a/src/amd/common/ac_llvm_build.h b/src/amd/common/ac_llvm_build.h
index 4eee9b32e9a01985b23159b8923f871b76e12e69..c080381d21ca3586fcfd8463516ce6c02c8a6342 100644 (file)
--- a/src/amd/common/ac_llvm_build.h
+++ b/src/amd/common/ac_llvm_build.h
@@ -43,6 +43,8 @@ enum {
        AC_CONST_32BIT_ADDR_SPACE = 6, /* same as CONST, but the pointer type has 32 bits */
 };
 
+struct ac_llvm_flow;
+
 struct ac_llvm_context {
        LLVMContextRef context;
        LLVMModuleRef module;
@@ -77,6 +79,10 @@ struct ac_llvm_context {
        LLVMValueRef i1true;
        LLVMValueRef i1false;
 
+       struct ac_llvm_flow *flow;
+       unsigned flow_depth;
+       unsigned flow_depth_max;
+
        unsigned range_md_kind;
        unsigned invariant_load_md_kind;
        unsigned uniform_md_kind;
@@ -94,6 +100,9 @@ void
 ac_llvm_context_init(struct ac_llvm_context *ctx, LLVMContextRef context,
                     enum chip_class chip_class, enum radeon_family family);
 
+void
+ac_llvm_context_dispose(struct ac_llvm_context *ctx);
+
 int
 ac_get_llvm_num_components(LLVMValueRef value);
 
@@ -370,6 +379,17 @@ LLVMValueRef ac_find_lsb(struct ac_llvm_context *ctx,
 LLVMTypeRef ac_array_in_const_addr_space(LLVMTypeRef elem_type);
 LLVMTypeRef ac_array_in_const32_addr_space(LLVMTypeRef elem_type);
 
+void ac_build_bgnloop(struct ac_llvm_context *ctx, int lable_id);
+void ac_build_break(struct ac_llvm_context *ctx);
+void ac_build_continue(struct ac_llvm_context *ctx);
+void ac_build_else(struct ac_llvm_context *ctx, int lable_id);
+void ac_build_endif(struct ac_llvm_context *ctx, int lable_id);
+void ac_build_endloop(struct ac_llvm_context *ctx, int lable_id);
+void ac_build_if(struct ac_llvm_context *ctx, LLVMValueRef value,
+                int lable_id);
+void ac_build_uif(struct ac_llvm_context *ctx, LLVMValueRef value,
+                 int lable_id);
+
 #ifdef __cplusplus
 }
 #endif

diff --git a/src/amd/common/ac_nir_to_llvm.c b/src/amd/common/ac_nir_to_llvm.c
index 0fbce5bbfd6f5f6bff4d6446f0814c43ab707b3e..9a3ce94af7ccba775b87e1a5f9548805a70017d6 100644 (file)
--- a/src/amd/common/ac_nir_to_llvm.c
+++ b/src/amd/common/ac_nir_to_llvm.c
@@ -6709,6 +6709,8 @@ static void ac_llvm_finalize_module(struct radv_shader_context *ctx)
 
        LLVMDisposeBuilder(ctx->ac.builder);
        LLVMDisposePassManager(passmgr);
+
+       ac_llvm_context_dispose(&ctx->ac);
 }
 
 static void