Add simple frame index elimination
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75939 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/SystemZ/SystemZRegisterInfo.cpp b/lib/Target/SystemZ/SystemZRegisterInfo.cpp
index 98bcf38..3773a2a 100644
--- a/lib/Target/SystemZ/SystemZRegisterInfo.cpp
+++ b/lib/Target/SystemZ/SystemZRegisterInfo.cpp
@@ -17,6 +17,7 @@
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/Target/TargetFrameInfo.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/ADT/BitVector.h"
@@ -77,9 +78,46 @@
assert(0 && "Not implemented yet!");
}
+int SystemZRegisterInfo::getFrameIndexOffset(MachineFunction &MF, int FI) const {
+ const TargetFrameInfo &TFI = *MF.getTarget().getFrameInfo();
+ MachineFrameInfo *MFI = MF.getFrameInfo();
+ int Offset = MFI->getObjectOffset(FI) + MFI->getOffsetAdjustment();
+ uint64_t StackSize = MFI->getStackSize();
+
+ Offset += StackSize - TFI.getOffsetOfLocalArea();
+
+ // Skip the register save area if we generated the stack frame.
+ if (StackSize)
+ Offset -= TFI.getOffsetOfLocalArea();
+
+ return Offset;
+}
+
void SystemZRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
int SPAdj, RegScavenger *RS) const {
- assert(0 && "Not implemented yet!");
+ assert(SPAdj == 0 && "Unxpected");
+
+ unsigned i = 0;
+ MachineInstr &MI = *II;
+ MachineFunction &MF = *MI.getParent()->getParent();
+ while (!MI.getOperand(i).isFI()) {
+ ++i;
+ assert(i < MI.getNumOperands() && "Instr doesn't have FrameIndex operand!");
+ }
+
+ int FrameIndex = MI.getOperand(i).getIndex();
+
+ unsigned BasePtr = (hasFP(MF) ? SystemZ::R11D : SystemZ::R15D);
+
+ // This must be part of a rri or ri operand memory reference. Replace the
+ // FrameIndex with base register with BasePtr. Add an offset to the
+ // displacement field.
+ MI.getOperand(i).ChangeToRegister(BasePtr, false);
+
+ // Offset is a 20-bit integer.
+ // FIXME: handle "too long" displacements.
+ int Offset = getFrameIndexOffset(MF, FrameIndex) + MI.getOperand(i+1).getImm();
+ MI.getOperand(i+1).ChangeToImmediate(Offset);
}
void SystemZRegisterInfo::emitPrologue(MachineFunction &MF) const {
diff --git a/lib/Target/SystemZ/SystemZRegisterInfo.h b/lib/Target/SystemZ/SystemZRegisterInfo.h
index 1af6f93..4de46bf 100644
--- a/lib/Target/SystemZ/SystemZRegisterInfo.h
+++ b/lib/Target/SystemZ/SystemZRegisterInfo.h
@@ -39,6 +39,8 @@
bool hasFP(const MachineFunction &MF) const;
+ int getFrameIndexOffset(MachineFunction &MF, int FI) const;
+
void eliminateCallFramePseudoInstr(MachineFunction &MF,
MachineBasicBlock &MBB,
MachineBasicBlock::iterator I) const;
diff --git a/lib/Target/SystemZ/SystemZTargetMachine.cpp b/lib/Target/SystemZ/SystemZTargetMachine.cpp
index a8b2b76..8160953 100644
--- a/lib/Target/SystemZ/SystemZTargetMachine.cpp
+++ b/lib/Target/SystemZ/SystemZTargetMachine.cpp
@@ -41,7 +41,7 @@
: Subtarget(*this, M, FS),
DataLayout("E-p:64:64:64-i1:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-f128:128:128"),
InstrInfo(*this), TLInfo(*this),
- FrameInfo(TargetFrameInfo::StackGrowsDown, 8, 0) {
+ FrameInfo(TargetFrameInfo::StackGrowsDown, 8, -160) {
}
bool SystemZTargetMachine::addInstSelector(PassManagerBase &PM,
diff --git a/test/CodeGen/SystemZ/06-FrameIdxLoad.ll b/test/CodeGen/SystemZ/06-FrameIdxLoad.ll
new file mode 100644
index 0000000..e475bf6
--- /dev/null
+++ b/test/CodeGen/SystemZ/06-FrameIdxLoad.ll
@@ -0,0 +1,16 @@
+; RUN: llvm-as < %s | llc | grep 160 | count 1
+; RUN: llvm-as < %s | llc | grep 168 | count 1
+
+target datalayout = "E-p:64:64:64-i1:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-f128:128:128"
+target triple = "s390x-unknown-linux-gnu"
+
+define i64 @foo(i64 %a, i64 %b, i64 %c, i64 %d, i64 %e, i64 %f, i64* %g) nounwind readnone {
+entry:
+ ret i64 %f
+}
+
+define i64 @bar(i64 %a, i64 %b, i64 %c, i64 %d, i64 %e, i64 %f, i64* %g) nounwind readnone {
+entry:
+ %conv = ptrtoint i64* %g to i64 ; <i64> [#uses=1]
+ ret i64 %conv
+}
diff --git a/test/CodeGen/SystemZ/06-LocalFrame.ll b/test/CodeGen/SystemZ/06-LocalFrame.ll
new file mode 100644
index 0000000..8c627db
--- /dev/null
+++ b/test/CodeGen/SystemZ/06-LocalFrame.ll
@@ -0,0 +1,12 @@
+; RUN: llvm-as < %s | llc | grep 160 | count 1
+; RUN: llvm-as < %s | llc | grep 328 | count 1
+
+target datalayout = "E-p:64:64:64-i1:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-f128:128:128"
+target triple = "s390x-unknown-linux-gnu"
+
+define noalias i64* @foo(i64 %a, i64 %b, i64 %c, i64 %d, i64 %e, i64 %f) nounwind readnone {
+entry:
+ %g = alloca i64, align 8 ; <i64*> [#uses=1]
+ %add.ptr = getelementptr i64* %g, i64 %f ; <i64*> [#uses=1]
+ ret i64* %add.ptr
+}