Subzero, MIPS32: Atomic intrinsics fixes

src/IceCfg.cpp

@@ -939,7 +939,7 @@ void Cfg::sortAndCombineAllocas(CfgVector<InstAlloca *> &Allocas,
       // Addressing is relative to the frame pointer.  Subtract the offset after
       // adding the size of the alloca, because it grows downwards from the
       // frame pointer.
-      Offsets.push_back(-(CurrentOffset + Size));
+      Offsets.push_back(Target->getFramePointerOffset(CurrentOffset, Size));
     } else {
       // Addressing is relative to the stack pointer or to a user pointer.  Add
       // the offset before adding the size of the object, because it grows

src/IceTargetLowering.h

@@ -253,7 +253,13 @@ public:
   virtual void reserveFixedAllocaArea(size_t Size, size_t Align) = 0;
   virtual int32_t getFrameFixedAllocaOffset() const = 0;
   virtual uint32_t maxOutArgsSizeBytes() const { return 0; }
-
+  // Addressing relative to frame pointer differs in MIPS compared to X86/ARM
+  // since MIPS decrements its stack pointer prior to saving it in the frame
+  // pointer register.
+  virtual uint32_t getFramePointerOffset(uint32_t CurrentOffset,
+                                         uint32_t Size) const {
+    return -(CurrentOffset + Size);
+  }
   /// Return whether a 64-bit Variable should be split into a Variable64On32.
   virtual bool shouldSplitToVariable64On32(Type Ty) const = 0;
 

src/IceTargetLoweringMIPS32.h

@@ -112,6 +112,12 @@ public:
 
   uint32_t maxOutArgsSizeBytes() const override { return MaxOutArgsSizeBytes; }
 
+  uint32_t getFramePointerOffset(uint32_t CurrentOffset,
+                                 uint32_t Size) const override {
+    (void)Size;
+    return CurrentOffset + MaxOutArgsSizeBytes;
+  }
+
   bool shouldSplitToVariable64On32(Type Ty) const override {
     return Ty == IceType_i64;
   }
@@ -613,6 +619,8 @@ public:
     void addiu_sp(uint32_t StackOffset);
     void lw(Variable *Dest, OperandMIPS32Mem *Mem);
     void sw(Variable *Dest, OperandMIPS32Mem *Mem);
+    void ll(Variable *Dest, OperandMIPS32Mem *Mem);
+    void sc(Variable *Dest, OperandMIPS32Mem *Mem);
     void lwc1(Variable *Dest, OperandMIPS32Mem *Mem, RelocOp Reloc = RO_No);
     void ldc1(Variable *Dest, OperandMIPS32Mem *Mem, RelocOp Reloc = RO_No);
     void ret(Variable *RetAddr, Variable *RetValue);

tests_lit/llvm2ice_tests/fused-alloca.ll

@@ -156,7 +156,7 @@ next:
 ; MIPS32: 	addiu	v0,sp,0
 ; MIPS32: 	addiu	v1,sp,16
 ; MIPS32: 	move	a1,a0
-; MIPS32: 	sw	a1,16(s8)
+; MIPS32: 	sw	a1,32(s8)
 ; MIPS32: 	move	a1,a0
 ; MIPS32: 	sw	a1,0(v0)
 ; MIPS32: 	sw	a0,0(v1)
@@ -221,9 +221,9 @@ next:
 ; MIPS32: 	move	a1,a0
 ; MIPS32: 	sw	a1,32(v0)
 ; MIPS32: 	move	v0,a0
-; MIPS32: 	sw	v0,64(s8)
+; MIPS32: 	sw	v0,80(s8)
 ; MIPS32: 	move	v0,a0
-; MIPS32: 	sw	v0,48(s8)
+; MIPS32: 	sw	v0,96(s8)
 ; MIPS32: 	sw	a0,0(v1)
 ; MIPS32: 	move	sp,s8
 ; MIPS32: 	lw	s8,{{.*}}(sp)