From 284eb57cfc30c4b6d39b4387ef3d10bec7dfb868 Mon Sep 17 00:00:00 2001
From: James Clarke <jrtc27@jrtc27.com>
Date: Tue, 31 Oct 2017 11:01:50 +0100
Subject: [PATCH] [Sparc] Account for bias in stack readjustment
---
lib/Target/Sparc/SparcFrameLowering.cpp | 29 ++++++++++++++++++++-----
test/CodeGen/SPARC/stack-align.ll | 16 +++++++++-----
2 files changed, 35 insertions(+), 10 deletions(-)
diff --git a/lib/Target/Sparc/SparcFrameLowering.cpp b/lib/Target/Sparc/SparcFrameLowering.cpp
index 122f830e0dc5..7399c93cb4d7 100644
--- a/lib/Target/Sparc/SparcFrameLowering.cpp
+++ b/lib/Target/Sparc/SparcFrameLowering.cpp
@@ -88,10 +88,11 @@ void SparcFrameLowering::emitPrologue(MachineFunction &MF,
assert(&MF.front() == &MBB && "Shrink-wrapping not yet supported");
MachineFrameInfo &MFI = MF.getFrameInfo();
+ const SparcSubtarget &Subtarget = MF.getSubtarget<SparcSubtarget>();
const SparcInstrInfo &TII =
- *static_cast<const SparcInstrInfo *>(MF.getSubtarget().getInstrInfo());
+ *static_cast<const SparcInstrInfo *>(Subtarget.getInstrInfo());
const SparcRegisterInfo &RegInfo =
- *static_cast<const SparcRegisterInfo *>(MF.getSubtarget().getRegisterInfo());
+ *static_cast<const SparcRegisterInfo *>(Subtarget.getRegisterInfo());
MachineBasicBlock::iterator MBBI = MBB.begin();
// Debug location must be unknown since the first debug location is used
// to determine the end of the prologue.
@@ -141,7 +142,7 @@ void SparcFrameLowering::emitPrologue(MachineFunction &MF,
// Adds the SPARC subtarget-specific spill area to the stack
// size. Also ensures target-required alignment.
- NumBytes = MF.getSubtarget<SparcSubtarget>().getAdjustedFrameSize(NumBytes);
+ NumBytes = Subtarget.getAdjustedFrameSize(NumBytes);
// Finally, ensure that the size is sufficiently aligned for the
// data on the stack.
@@ -176,9 +177,27 @@ void SparcFrameLowering::emitPrologue(MachineFunction &MF,
.addCFIIndex(CFIIndex);
if (NeedsStackRealignment) {
- // andn %o6, MaxAlign-1, %o6
+ int64_t Bias = Subtarget.getStackPointerBias();
+ unsigned regUnbiased;
+ if (Bias) {
+ // This clobbers G1 which we always know is available here.
+ regUnbiased = SP::G1;
+ // add %o6, BIAS, %g1
+ BuildMI(MBB, MBBI, dl, TII.get(SP::ADDri), regUnbiased)
+ .addReg(SP::O6).addImm(Bias);
+ } else
+ regUnbiased = SP::O6;
+
+ // andn %regUnbiased, MaxAlign-1, %regUnbiased
int MaxAlign = MFI.getMaxAlignment();
- BuildMI(MBB, MBBI, dl, TII.get(SP::ANDNri), SP::O6).addReg(SP::O6).addImm(MaxAlign - 1);
+ BuildMI(MBB, MBBI, dl, TII.get(SP::ANDNri), regUnbiased)
+ .addReg(regUnbiased).addImm(MaxAlign - 1);
+
+ if (Bias) {
+ // add %o6, -BIAS, %g1
+ BuildMI(MBB, MBBI, dl, TII.get(SP::ADDri), SP::O6)
+ .addReg(regUnbiased).addImm(-Bias);
+ }
}
}
diff --git a/test/CodeGen/SPARC/stack-align.ll b/test/CodeGen/SPARC/stack-align.ll
index b152e6a038f5..6516fb78e48b 100644
--- a/test/CodeGen/SPARC/stack-align.ll
+++ b/test/CodeGen/SPARC/stack-align.ll
@@ -1,4 +1,5 @@
-; RUN: llc -march=sparc < %s | FileCheck %s
+; RUN: llc -march=sparc < %s | FileCheck %s --check-prefixes=CHECK,CHECK32
+; RUN: llc -march=sparcv9 < %s | FileCheck %s --check-prefixes=CHECK,CHECK64
declare void @stack_realign_helper(i32 %a, i32* %b)
;; This is a function where we have a local variable of 64-byte
@@ -7,10 +8,15 @@ declare void @stack_realign_helper(i32 %a, i32* %b)
;; the argument is accessed via frame pointer not stack pointer (to %o0).
;; CHECK-LABEL: stack_realign:
-;; CHECK: andn %sp, 63, %sp
-;; CHECK-NEXT: ld [%fp+92], %o0
-;; CHECK-NEXT: call stack_realign_helper
-;; CHECK-NEXT: add %sp, 128, %o1
+;; CHECK32: andn %sp, 63, %sp
+;; CHECK32-NEXT: ld [%fp+92], %o0
+;; CHECK64: add %sp, 2047, %g1
+;; CHECK64-NEXT: andn %g1, 63, %g1
+;; CHECK64-NEXT: add %g1, -2047, %sp
+;; CHECK64-NEXT: ld [%fp+2227], %o0
+;; CHECK-NEXT: call stack_realign_helper
+;; CHECK32-NEXT: add %sp, 128, %o1
+;; CHECK64-NEXT: add %sp, 2239, %o1
define void @stack_realign(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e, i32 %f, i32 %g) {
entry: