[Mesa-dev] [PATCH 2/4] radv/ac: use shader imsb emission code.

[Dave Airlie]

From: Dave Airlie <airlied at redhat.com>

Signed-off-by: Dave Airlie <airlied at redhat.com>
---
 src/amd/common/ac_nir_to_llvm.c | 18 +-----------------
 1 file changed, 1 insertion(+), 17 deletions(-)

diff --git a/src/amd/common/ac_nir_to_llvm.c b/src/amd/common/ac_nir_to_llvm.c
index 0564dd1..b28812e 100644
--- a/src/amd/common/ac_nir_to_llvm.c
+++ b/src/amd/common/ac_nir_to_llvm.c
@@ -931,23 +931,7 @@ static LLVMValueRef emit_find_lsb(struct nir_to_llvm_context *ctx,
 static LLVMValueRef emit_ifind_msb(struct nir_to_llvm_context *ctx,
 				   LLVMValueRef src0)
 {
-	LLVMValueRef msb = ac_emit_llvm_intrinsic(&ctx->ac, "llvm.AMDGPU.flbit.i32",
-					       ctx->i32, &src0, 1,
-					       AC_FUNC_ATTR_READNONE);
-
-	/* The HW returns the last bit index from MSB, but NIR wants
-	 * the index from LSB. Invert it by doing "31 - msb". */
-	msb = LLVMBuildSub(ctx->builder, LLVMConstInt(ctx->i32, 31, false),
-			   msb, "");
-
-	LLVMValueRef all_ones = LLVMConstInt(ctx->i32, -1, true);
-	LLVMValueRef cond = LLVMBuildOr(ctx->builder,
-					LLVMBuildICmp(ctx->builder, LLVMIntEQ,
-						      src0, ctx->i32zero, ""),
-					LLVMBuildICmp(ctx->builder, LLVMIntEQ,
-						      src0, all_ones, ""), "");
-
-	return LLVMBuildSelect(ctx->builder, cond, all_ones, msb, "");
+	return ac_emit_imsb(&ctx->ac, src0, ctx->i32);
 }
 
 static LLVMValueRef emit_ufind_msb(struct nir_to_llvm_context *ctx,
-- 
2.7.4