[llvm] r319014 - [ARM] Fix an off-by-one error when restoring LR for 16-bit Thumb
Momchil Velikov via llvm-commits
llvm-commits at lists.llvm.org
Mon Nov 27 02:13:14 PST 2017
Author: chill
Date: Mon Nov 27 02:13:14 2017
New Revision: 319014
URL: http://llvm.org/viewvc/llvm-project?rev=319014&view=rev
Log:
[ARM] Fix an off-by-one error when restoring LR for 16-bit Thumb
The commit https://reviews.llvm.org/rL318143 computes incorrectly to offset to
restore LR from.
The number of tPOP operands is 2 (condition) + 2 (implicit def and use of SP) +
count of the popped registers. We need to load LR from just past the last
register, hence the correct offset should be either getNumOperands() - 4 and
getNumExplicitOperands() - 2 (multiplied by 4).
Differential revision: https://reviews.llvm.org/D40305
Modified:
llvm/trunk/lib/Target/ARM/Thumb1FrameLowering.cpp
llvm/trunk/test/CodeGen/ARM/thumb1_return_sequence.ll
llvm/trunk/test/CodeGen/ARM/v8m-tail-call.ll
llvm/trunk/test/CodeGen/Thumb/thumb-shrink-wrapping.ll
Modified: llvm/trunk/lib/Target/ARM/Thumb1FrameLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/Thumb1FrameLowering.cpp?rev=319014&r1=319013&r2=319014&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/Thumb1FrameLowering.cpp (original)
+++ llvm/trunk/lib/Target/ARM/Thumb1FrameLowering.cpp Mon Nov 27 02:13:14 2017
@@ -647,7 +647,7 @@ bool Thumb1FrameLowering::emitPopSpecial
BuildMI(MBB, MBBI, dl, TII.get(ARM::tLDRspi))
.addReg(PopReg, RegState::Define)
.addReg(ARM::SP)
- .addImm(MBBI->getNumOperands() - 3)
+ .addImm(MBBI->getNumExplicitOperands() - 2)
.add(predOps(ARMCC::AL));
// Move from the temporary register to the LR.
BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr))
Modified: llvm/trunk/test/CodeGen/ARM/thumb1_return_sequence.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/ARM/thumb1_return_sequence.ll?rev=319014&r1=319013&r2=319014&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/ARM/thumb1_return_sequence.ll (original)
+++ llvm/trunk/test/CodeGen/ARM/thumb1_return_sequence.ll Mon Nov 27 02:13:14 2017
@@ -25,7 +25,7 @@ entry:
; --------
; Stack realignment means sp is restored from frame pointer
; CHECK-V4T: mov sp
-; CHECK-V4T-NEXT: ldr [[POP:r[4567]]], [sp, #{{.*}}]
+; CHECK-V4T-NEXT: ldr [[POP:r[4567]]], [sp, #16]
; CHECK-V4T-NEXT: mov lr, [[POP]]
; CHECK-V4T-NEXT: pop {[[SAVED]]}
; CHECK-V4T-NEXT add sp, sp, #4
@@ -57,14 +57,14 @@ entry:
; Epilogue
; --------
-; CHECK-V4T: ldr [[POP:r[4567]]], [sp, #{{.*}}]
+; CHECK-V4T: ldr [[POP:r[4567]]], [sp, #12]
; CHECK-V4T-NEXT: mov lr, [[POP]]
; CHECK-V4T-NEXT: pop {[[SAVED]]}
; CHECK-V4T-NEXT: add sp, #16
; CHECK-V4T-NEXT: bx lr
; CHECK-V5T: lsls r4
; CHECK-V5T-NEXT: mov sp, r4
-; CHECK-V5T: ldr [[POP:r[4567]]], [sp, #{{.*}}]
+; CHECK-V5T: ldr [[POP:r[4567]]], [sp, #12]
; CHECK-V5T-NEXT: mov lr, [[POP]]
; CHECK-V5T-NEXT: pop {[[SAVED]]}
; CHECK-V5T-NEXT: add sp, #16
Modified: llvm/trunk/test/CodeGen/ARM/v8m-tail-call.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/ARM/v8m-tail-call.ll?rev=319014&r1=319013&r2=319014&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/ARM/v8m-tail-call.ll (original)
+++ llvm/trunk/test/CodeGen/ARM/v8m-tail-call.ll Mon Nov 27 02:13:14 2017
@@ -8,7 +8,7 @@ define hidden i32 @f0() {
%2 = tail call i32 @h0(i32 %1, i32 1, i32 2, i32 3)
ret i32 %2
; CHECK-LABEL: f0
-; CHECK: ldr [[POP:r[4567]]], [sp
+; CHECK: ldr [[POP:r[4567]]], [sp, #4]
; CHECK-NEXT: mov lr, [[POP]]
; CHECK-NEXT: pop {{.*}}[[POP]]
; CHECK-NEXT: add sp, #4
@@ -39,7 +39,7 @@ define hidden i32 @f2(i32, i32, i32, i32
%11 = phi i32 [ %9, %8 ], [ -1, %5 ]
ret i32 %11
; CHECK-LABEL: f2
-; CHECK: ldr [[POP:r[4567]]], [sp
+; CHECK: ldr [[POP:r[4567]]], [sp, #12]
; CHECK-NEXT: mov lr, [[POP]]
; CHECK-NEXT: pop {{.*}}[[POP]]
; CHECK-NEXT: add sp, #4
Modified: llvm/trunk/test/CodeGen/Thumb/thumb-shrink-wrapping.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/Thumb/thumb-shrink-wrapping.ll?rev=319014&r1=319013&r2=319014&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/Thumb/thumb-shrink-wrapping.ll (original)
+++ llvm/trunk/test/CodeGen/Thumb/thumb-shrink-wrapping.ll Mon Nov 27 02:13:14 2017
@@ -647,7 +647,7 @@ define i1 @beq_to_bx(i32* %y, i32 %head)
; ENABLE: push {r4, lr}
; CHECK: tst r3, r4
-; ENABLE-NEXT: ldr [[POP:r[4567]]], [sp, #8]
+; ENABLE-NEXT: ldr [[POP:r[4567]]], [sp, #4]
; ENABLE-NEXT: mov lr, [[POP]]
; ENABLE-NEXT: pop {[[POP]]}
; ENABLE-NEXT: add sp, #4
More information about the llvm-commits
mailing list