This patch adds a new NVPTX back-end to LLVM which supports code generation for NVIDIA PTX 3.0. This back-end will (eventually) replace the current PTX back-end, while maintaining compatibility with it.
The new target machines are:
nvptx (old ptx32) => 32-bit PTX
nvptx64 (old ptx64) => 64-bit PTX
The sources are based on the internal NVIDIA NVPTX back-end, and
contain more functionality than the current PTX back-end currently
provides.
NV_CONTRIB
llvm-svn: 156196
diff --git a/llvm/lib/Target/NVPTX/NVPTXutil.cpp b/llvm/lib/Target/NVPTX/NVPTXutil.cpp
new file mode 100644
index 0000000..de311d2
--- /dev/null
+++ b/llvm/lib/Target/NVPTX/NVPTXutil.cpp
@@ -0,0 +1,91 @@
+//===-- NVPTXutil.cpp - Functions exported to CodeGen --*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains the functions that can be used in CodeGen.
+//
+//===----------------------------------------------------------------------===//
+
+#include "NVPTXutil.h"
+#include "NVPTX.h"
+
+using namespace llvm;
+
+namespace llvm {
+
+bool isParamLoad(const MachineInstr *MI)
+{
+ if ((MI->getOpcode() != NVPTX::LD_i32_avar) &&
+ (MI->getOpcode() != NVPTX::LD_i64_avar))
+ return false;
+ if (MI->getOperand(2).isImm() == false)
+ return false;
+ if (MI->getOperand(2).getImm() != NVPTX::PTXLdStInstCode::PARAM)
+ return false;
+ return true;
+}
+
+#define DATA_MASK 0x7f
+#define DIGIT_WIDTH 7
+#define MORE_BYTES 0x80
+
+static int encode_leb128(uint64_t val, int *nbytes,
+ char *space, int splen)
+{
+ char *a;
+ char *end = space + splen;
+
+ a = space;
+ do {
+ unsigned char uc;
+
+ if (a >= end)
+ return 1;
+ uc = val & DATA_MASK;
+ val >>= DIGIT_WIDTH;
+ if (val != 0)
+ uc |= MORE_BYTES;
+ *a = uc;
+ a++;
+ } while (val);
+ *nbytes = a - space;
+ return 0;
+}
+
+#undef DATA_MASK
+#undef DIGIT_WIDTH
+#undef MORE_BYTES
+
+uint64_t encode_leb128(const char *str)
+{
+ union { uint64_t x; char a[8]; } temp64;
+
+ temp64.x = 0;
+
+ for (unsigned i=0,e=strlen(str); i!=e; ++i)
+ temp64.a[i] = str[e-1-i];
+
+ char encoded[16];
+ int nbytes;
+
+ int retval = encode_leb128(temp64.x, &nbytes, encoded, 16);
+
+ assert(retval == 0 &&
+ "Encoding to leb128 failed");
+
+ assert(nbytes <= 8 &&
+ "Cannot support register names with leb128 encoding > 8 bytes");
+
+ temp64.x = 0;
+ for (int i=0; i<nbytes; ++i)
+ temp64.a[i] = encoded[i];
+
+ return temp64.x;
+}
+
+} // end namespace llvm