From: Tim Northover <tnorthover@apple.com>
Date: Wed, 18 Nov 2015 21:10:39 +0000 (+0000)
Subject: ARM: make sure backend is consistent about exception handling method.
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=c931f35508d5a7eb6337f5c8845f470afb4da6a6;p=oota-llvm.git

ARM: make sure backend is consistent about exception handling method.

It turns out we decide whether to use SjLj exceptions or some alternative in
two separate places in the backend, and they disagreed with each other. This
led to inconsistent code and is generally a terrible idea.

So make them consistent and add an assert that they *do* match (unfortunately
MCAsmInfo isn't available in opt, so it can't be used to initialise the CodeGen
version directly).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253502 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/ARM/ARMSubtarget.cpp b/lib/Target/ARM/ARMSubtarget.cpp
index 52b188949fb..9e3cd36d49e 100644
--- a/lib/Target/ARM/ARMSubtarget.cpp
+++ b/lib/Target/ARM/ARMSubtarget.cpp
@@ -26,6 +26,7 @@
 #include "llvm/IR/Attributes.h"
 #include "llvm/IR/Function.h"
 #include "llvm/IR/GlobalValue.h"
+#include "llvm/MC/MCAsmInfo.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Target/TargetInstrInfo.h"
 #include "llvm/Target/TargetOptions.h"
@@ -151,8 +152,15 @@ void ARMSubtarget::initializeEnvironment() {
   UseNaClTrap = false;
   GenLongCalls = false;
   UnsafeFPMath = false;
-  UseSjLjEH = (isTargetDarwin() &&
-               TargetTriple.getSubArch() != Triple::ARMSubArch_v7k);
+
+  // MCAsmInfo isn't always present (e.g. in opt) so we can't initialize this
+  // directly from it, but we can try to make sure they're consistent when both
+  // available.
+  UseSjLjEH = isTargetDarwin() && !isTargetWatchOS();
+  assert((!TM.getMCAsmInfo() ||
+          (TM.getMCAsmInfo()->getExceptionHandlingType() ==
+           ExceptionHandling::SjLj) == UseSjLjEH) &&
+         "inconsistent sjlj choice between CodeGen and MC");
 }
 
 void ARMSubtarget::initSubtargetFeatures(StringRef CPU, StringRef FS) {
diff --git a/lib/Target/ARM/MCTargetDesc/ARMMCAsmInfo.cpp b/lib/Target/ARM/MCTargetDesc/ARMMCAsmInfo.cpp
index 2114fa96473..bda37f6616a 100644
--- a/lib/Target/ARM/MCTargetDesc/ARMMCAsmInfo.cpp
+++ b/lib/Target/ARM/MCTargetDesc/ARMMCAsmInfo.cpp
@@ -33,8 +33,9 @@ ARMMCAsmInfoDarwin::ARMMCAsmInfoDarwin(const Triple &TheTriple) {
   SupportsDebugInformation = true;
 
   // Exceptions handling
-  ExceptionsType = TheTriple.isWatchOS() ? ExceptionHandling::DwarfCFI
-                                         : ExceptionHandling::SjLj;
+  ExceptionsType = TheTriple.isOSDarwin() && !TheTriple.isWatchOS()
+                       ? ExceptionHandling::SjLj
+                       : ExceptionHandling::DwarfCFI;
 
   UseIntegratedAssembler = true;
 }
diff --git a/test/CodeGen/ARM/eh-resume-darwin.ll b/test/CodeGen/ARM/eh-resume-darwin.ll
index 6ac025c6f05..d3a8481275f 100644
--- a/test/CodeGen/ARM/eh-resume-darwin.ll
+++ b/test/CodeGen/ARM/eh-resume-darwin.ll
@@ -1,4 +1,5 @@
 ; RUN: llc < %s -mtriple=armv7-apple-ios -arm-atomic-cfg-tidy=0 | FileCheck %s -check-prefix=IOS
+; RUN: llc < %s -mtriple=armv7k-apple-ios -arm-atomic-cfg-tidy=0 | FileCheck %s -check-prefix=IOS
 ; RUN: llc < %s -mtriple=armv7k-apple-watchos -arm-atomic-cfg-tidy=0 | FileCheck %s -check-prefix=WATCHOS
 
 declare void @func()
diff --git a/test/CodeGen/ARM/sjljehprepare-lower-empty-struct.ll b/test/CodeGen/ARM/sjljehprepare-lower-empty-struct.ll
index 5d015738623..b44b447b3df 100644
--- a/test/CodeGen/ARM/sjljehprepare-lower-empty-struct.ll
+++ b/test/CodeGen/ARM/sjljehprepare-lower-empty-struct.ll
@@ -2,6 +2,7 @@
 ; RUN: llc -mtriple=armv7-apple-ios -O1 < %s | FileCheck %s
 ; RUN: llc -mtriple=armv7-apple-ios -O2 < %s | FileCheck %s
 ; RUN: llc -mtriple=armv7-apple-ios -O3 < %s | FileCheck %s
+; RUN: llc -mtriple=armv7k-apple-ios < %s | FileCheck %s
 
 ; SjLjEHPrepare shouldn't crash when lowering empty structs.
 ;
diff --git a/test/CodeGen/Thumb/thumb-shrink-wrapping.ll b/test/CodeGen/Thumb/thumb-shrink-wrapping.ll
index 62f78258e7d..09c2ae3b4f7 100644
--- a/test/CodeGen/Thumb/thumb-shrink-wrapping.ll
+++ b/test/CodeGen/Thumb/thumb-shrink-wrapping.ll
@@ -22,7 +22,7 @@
 ;
 ; Prologue code.
 ; CHECK: push {r7, lr}
-; CHECK-NEXT: sub sp, #8
+; CHECK: sub sp, #8
 ;
 ; Compare the arguments and jump to exit.
 ; After the prologue is set.
@@ -418,7 +418,7 @@ if.end:                                           ; preds = %for.body, %if.else
 ;
 ; Prologue code.
 ; CHECK: push {[[TMP:r[0-9]+]], lr}
-; CHECK-NEXT: sub sp, #16
+; CHECK: sub sp, #16
 ;
 ; DISABLE: cmp r0, #0
 ; DISABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]