Doubleword Shift Left Logical Plus 32

Mips shift instructions DSLL, DSRL and DSRA are transformed into
DSLL32, DSRL32 and DSRA32 respectively if the shift amount is between
32 and 63

Here is a description of DSLL:

Purpose: Doubleword Shift Left Logical Plus 32
To execute a left-shift of a doubleword by a fixed amount--32 to 63 bits

Description: GPR[rd] <- GPR[rt] << (sa+32)

The 64-bit doubleword contents of GPR rt are shifted left, inserting
 zeros into the emptied bits; the result is placed in
GPR rd. The bit-shift amount in the range 0 to 31 is specified by sa.

This patch implements the direct object output of these instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160277 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/Mips/Mips64InstrInfo.td b/lib/Target/Mips/Mips64InstrInfo.td
index 7a9d41bae8f7490aae213af6c3d89678f9a90f21..cceee24a7481ce9e4e38760c244167be148c381a 100644 (file)
--- a/lib/Target/Mips/Mips64InstrInfo.td
+++ b/lib/Target/Mips/Mips64InstrInfo.td
@@ -109,6 +109,11 @@ def DSRA     : shift_rotate_imm64<0x3b, 0x00, "dsra", sra>;
 def DSLLV    : shift_rotate_reg<0x14, 0x00, "dsllv", shl, CPU64Regs>;
 def DSRLV    : shift_rotate_reg<0x16, 0x00, "dsrlv", srl, CPU64Regs>;
 def DSRAV    : shift_rotate_reg<0x17, 0x00, "dsrav", sra, CPU64Regs>;
+let Pattern = []<dag> in {
+def DSLL32   : shift_rotate_imm64<0x3c, 0x00, "dsll32", shl>;
+def DSRL32   : shift_rotate_imm64<0x3e, 0x00, "dsrl32", srl>;
+def DSRA32   : shift_rotate_imm64<0x3f, 0x00, "dsra32", sra>;
+}
 }
 // Rotate Instructions
 let Predicates = [HasMips64r2, HasStandardEncoding],

diff --git a/lib/Target/Mips/MipsAsmPrinter.cpp b/lib/Target/Mips/MipsAsmPrinter.cpp
index 4dac59105de35e029410675f64e3943f2a4f6703..914a204fe2ef1249e1b55f67e3d42c9acc26ec1f 100644 (file)
--- a/lib/Target/Mips/MipsAsmPrinter.cpp
+++ b/lib/Target/Mips/MipsAsmPrinter.cpp
@@ -13,9 +13,10 @@
 //===----------------------------------------------------------------------===//
 
 #define DEBUG_TYPE "mips-asm-printer"
-#include "MipsAsmPrinter.h"
 #include "Mips.h"
+#include "MipsAsmPrinter.h"
 #include "MipsInstrInfo.h"
+#include "MipsMCInstLower.h"
 #include "InstPrinter/MipsInstPrinter.h"
 #include "MCTargetDesc/MipsBaseInfo.h"
 #include "llvm/ADT/SmallString.h"
@@ -57,6 +58,25 @@ void MipsAsmPrinter::EmitInstruction(const MachineInstr *MI) {
     return;
   }
 
+  // Direct object specific instruction lowering
+  if (!OutStreamer.hasRawTextSupport())
+    switch (MI->getOpcode()) {
+    case Mips::DSLL:
+    case Mips::DSRL:
+    case Mips::DSRA:
+      assert(MI->getNumOperands() == 3 &&
+             "Invalid no. of machine operands for shift!");
+      assert(MI->getOperand(2).isImm());
+      int64_t Shift = MI->getOperand(2).getImm();
+      if (Shift > 31) {
+        MCInst TmpInst0;
+        MCInstLowering.LowerLargeShift(MI, TmpInst0, Shift - 32);
+        OutStreamer.EmitInstruction(TmpInst0);
+        return;
+      }
+      break;
+    }
+
   MachineBasicBlock::const_instr_iterator I = MI;
   MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end();
 

diff --git a/lib/Target/Mips/MipsMCInstLower.cpp b/lib/Target/Mips/MipsMCInstLower.cpp
index b6042af619d30c9164262a6c4e895e0b8ad6e14f..c49d5308a5b0db2a369a67fc34a58a053c0b4b2b 100644 (file)
--- a/lib/Target/Mips/MipsMCInstLower.cpp
+++ b/lib/Target/Mips/MipsMCInstLower.cpp
@@ -158,3 +158,32 @@ void MipsMCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const {
       OutMI.addOperand(MCOp);
   }
 }
+
+// If the D<shift> instruction has a shift amount that is greater
+// than 31 (checked in calling routine), lower it to a D<shift>32 instruction
+void MipsMCInstLower::LowerLargeShift(const MachineInstr *MI,
+                                      MCInst& Inst,
+                                      int64_t Shift) {
+  // rt
+  Inst.addOperand(LowerOperand(MI->getOperand(0)));
+  // rd
+  Inst.addOperand(LowerOperand(MI->getOperand(1)));
+  // saminus32
+  Inst.addOperand(MCOperand::CreateImm(Shift));
+
+  switch (MI->getOpcode()) {
+  default:
+    // Calling function is not synchronized
+    llvm_unreachable("Unexpected shift instruction");
+    break;
+  case Mips::DSLL:
+    Inst.setOpcode(Mips::DSLL32);
+    break;
+  case Mips::DSRL:
+    Inst.setOpcode(Mips::DSRL32);
+    break;
+  case Mips::DSRA:
+    Inst.setOpcode(Mips::DSRA32);
+    break;
+  }
+}

diff --git a/lib/Target/Mips/MipsMCInstLower.h b/lib/Target/Mips/MipsMCInstLower.h
index 314420a170422a1b82eb5e2eb75335f5f1ccc0b1..0abb996a6877532ce1caecdcb9db95067d1b1d98 100644 (file)
--- a/lib/Target/Mips/MipsMCInstLower.h
+++ b/lib/Target/Mips/MipsMCInstLower.h
@@ -33,6 +33,8 @@ public:
   MipsMCInstLower(MipsAsmPrinter &asmprinter);
   void Initialize(Mangler *mang, MCContext *C);
   void Lower(const MachineInstr *MI, MCInst &OutMI) const;
+  void LowerLargeShift(const MachineInstr *MI, MCInst &Inst, int64_t Shift);
+
 private:
   MCOperand LowerSymbolOperand(const MachineOperand &MO,
                                MachineOperandType MOTy, unsigned Offset) const;

diff --git a/test/MC/Mips/mips64shift.ll b/test/MC/Mips/mips64shift.ll
new file mode 100644 (file)
index 0000000..7817b96
--- /dev/null
+++ b/test/MC/Mips/mips64shift.ll
@@ -0,0 +1,45 @@
+; RUN: llc -march=mips64el -filetype=obj -mcpu=mips64r2 %s -o - | llvm-objdump -disassemble -triple mips64el - | FileCheck %s
+
+
+define i64 @f3(i64 %a0) nounwind readnone {
+entry:
+; CHECK: dsll ${{[0-9]+}}, ${{[0-9]+}}, 10
+  %shl = shl i64 %a0, 10
+  ret i64 %shl
+}
+
+define i64 @f4(i64 %a0) nounwind readnone {
+entry:
+; CHECK: dsra ${{[0-9]+}}, ${{[0-9]+}}, 10
+  %shr = ashr i64 %a0, 10
+  ret i64 %shr
+}
+
+define i64 @f5(i64 %a0) nounwind readnone {
+entry:
+; CHECK: dsrl ${{[0-9]+}}, ${{[0-9]+}}, 10
+  %shr = lshr i64 %a0, 10
+  ret i64 %shr
+}
+
+define i64 @f6(i64 %a0) nounwind readnone {
+entry:
+; CHECK: dsll32 ${{[0-9]+}}, ${{[0-9]+}}, 8
+  %shl = shl i64 %a0, 40
+  ret i64 %shl
+}
+
+define i64 @f7(i64 %a0) nounwind readnone {
+entry:
+; CHECK: dsra32 ${{[0-9]+}}, ${{[0-9]+}}, 8
+  %shr = ashr i64 %a0, 40
+  ret i64 %shr
+}
+
+define i64 @f8(i64 %a0) nounwind readnone {
+entry:
+; CHECK: dsrl32 ${{[0-9]+}}, ${{[0-9]+}}, 8
+  %shr = lshr i64 %a0, 40
+  ret i64 %shr
+}
+