[llvm-branch-commits] [llvm-branch] r324090 - Merging r323643:

Fri Feb 2 05:56:46 PST 2018

Author: hans
Date: Fri Feb  2 05:56:46 2018
New Revision: 324090

URL: http://llvm.org/viewvc/llvm-project?rev=324090&view=rev
Log:
Merging r323643:
------------------------------------------------------------------------
r323643 | jdevlieghere | 2018-01-29 13:10:32 +0100 (Mon, 29 Jan 2018) | 16 lines

[Sparc] Account for bias in stack readjustment

Summary: This was broken long ago in D12208, which failed to account for
the fact that 64-bit SPARC uses a stack bias of 2047, and it is the
*unbiased* value which should be aligned, not the biased one. This was
seen to be an issue with Rust.

Patch by: jrtc27 (James Clarke)

Reviewers: jyknight, venkatra

Reviewed By: jyknight

Subscribers: jacob_hansen, JDevlieghere, fhahn, fedor.sergeev, llvm-commits

Differential Revision: https://reviews.llvm.org/D39425
------------------------------------------------------------------------

Modified:
    llvm/branches/release_60/   (props changed)
    llvm/branches/release_60/lib/Target/Sparc/SparcFrameLowering.cpp
    llvm/branches/release_60/test/CodeGen/SPARC/stack-align.ll

Propchange: llvm/branches/release_60/
------------------------------------------------------------------------------

--- svn:mergeinfo (original)
+++ svn:mergeinfo Fri Feb  2 05:56:46 2018
@@ -1,3 +1,3 @@
 /llvm/branches/Apple/Pertwee:110850,110961
 /llvm/branches/type-system-rewrite:133420-134817
-/llvm/trunk:155241,321751,321789,321791,321806,321862,321870,321872,321878,321980,321991,321993-321994,322003,322016,322053,322056,322103,322106,322108,322123,322131,322223,322272,322313,322372,322473,322623,322644,322724,322767,322875,322878-322879,322900,322904-322905,322973,322993,323034,323155,323190,323307,323331,323355,323369,323371,323384,323469,323515,323536,323582,323671-323672,323706,323710,323759,323781,323810-323811,323813,323857,323907,323909,323913,323915
+/llvm/trunk:155241,321751,321789,321791,321806,321862,321870,321872,321878,321980,321991,321993-321994,322003,322016,322053,322056,322103,322106,322108,322123,322131,322223,322272,322313,322372,322473,322623,322644,322724,322767,322875,322878-322879,322900,322904-322905,322973,322993,323034,323155,323190,323307,323331,323355,323369,323371,323384,323469,323515,323536,323582,323643,323671-323672,323706,323710,323759,323781,323810-323811,323813,323857,323907,323909,323913,323915

Modified: llvm/branches/release_60/lib/Target/Sparc/SparcFrameLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_60/lib/Target/Sparc/SparcFrameLowering.cpp?rev=324090&r1=324089&r2=324090&view=diff
==============================================================================
--- llvm/branches/release_60/lib/Target/Sparc/SparcFrameLowering.cpp (original)
+++ llvm/branches/release_60/lib/Target/Sparc/SparcFrameLowering.cpp Fri Feb  2 05:56:46 2018
@@ -88,10 +88,11 @@ void SparcFrameLowering::emitPrologue(Ma
 
   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(Ma
 
   // 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(Ma
       .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 %g1, -BIAS, %o6
+      BuildMI(MBB, MBBI, dl, TII.get(SP::ADDri), SP::O6)
+        .addReg(regUnbiased).addImm(-Bias);
+    }
   }
 }
 

Modified: llvm/branches/release_60/test/CodeGen/SPARC/stack-align.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_60/test/CodeGen/SPARC/stack-align.ll?rev=324090&r1=324089&r2=324090&view=diff
==============================================================================
--- llvm/branches/release_60/test/CodeGen/SPARC/stack-align.ll (original)
+++ llvm/branches/release_60/test/CodeGen/SPARC/stack-align.ll Fri Feb  2 05:56:46 2018
@@ -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 %
 ;; 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:


