ac/llvm: fix missing casts in ac_build_readlane()

Because ac_build_optimization_barrier() overwrites the original
src_type, we have to keep track of it before emitting that barrier.
Otherwise, wrong conversions are expected for pointers or small
bitsizes.

By doing this, we no longer need to do the cast dance in
ac_build_readlane_no_opt_barrier(), it was just necessary for
ac_build_optimization_barrier().

This fixes a bunch of crashes with subgroups related tests when
RADV_DEBUG=checkir is enabled, and it also fixes a compiler crash
with The Surge 2.

Closes: https://gitlab.freedesktop.org/mesa/mesa/issues/2395
Fixes: 0f45d4dc2b1 ("ac: add ac_build_readlane without optimization barrier")
Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Acked-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3535>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3535>

diff --git a/src/amd/llvm/ac_llvm_build.c b/src/amd/llvm/ac_llvm_build.c
index 33cec6b878d2271d48729ba1be28568d7683816d..8d706944a453be6caff08f225ab9f644f2f52615 100644 (file)
--- a/src/amd/llvm/ac_llvm_build.c
+++ b/src/amd/llvm/ac_llvm_build.c
@@ -3623,8 +3623,6 @@ _ac_build_readlane(struct ac_llvm_context *ctx, LLVMValueRef src, LLVMValueRef l
 LLVMValueRef ac_build_readlane_no_opt_barrier(struct ac_llvm_context *ctx,
                                              LLVMValueRef src, LLVMValueRef lane)
 {
-       LLVMTypeRef src_type = LLVMTypeOf(src);
-       src = ac_to_integer(ctx, src);
        unsigned bits = LLVMGetIntTypeWidth(LLVMTypeOf(src));
        LLVMValueRef ret;
 
@@ -3645,17 +3643,22 @@ LLVMValueRef ac_build_readlane_no_opt_barrier(struct ac_llvm_context *ctx,
                ret = _ac_build_readlane(ctx, src, lane);
        }
 
-       if (LLVMGetTypeKind(src_type) == LLVMPointerTypeKind)
-               return LLVMBuildIntToPtr(ctx->builder, ret, src_type, "");
-       return LLVMBuildBitCast(ctx->builder, ret, src_type, "");
+       return ret;
 }
 
 LLVMValueRef
 ac_build_readlane(struct ac_llvm_context *ctx, LLVMValueRef src, LLVMValueRef lane)
 {
+       LLVMTypeRef src_type = LLVMTypeOf(src);
+       src = ac_to_integer(ctx, src);
+       LLVMValueRef ret;
+
        ac_build_optimization_barrier(ctx, &src);
 
-       return ac_build_readlane_no_opt_barrier(ctx, src, lane);
+       ret = ac_build_readlane_no_opt_barrier(ctx, src, lane);
+       if (LLVMGetTypeKind(src_type) == LLVMPointerTypeKind)
+               return LLVMBuildIntToPtr(ctx->builder, ret, src_type, "");
+       return LLVMBuildBitCast(ctx->builder, ret, src_type, "");
 }
 
 LLVMValueRef