[ARM] Allow execute only code on Cortex-m23

The NoMovt feature prevents the use of MOVW/MOVT
instructions on Cortex-M23 for performance reasons.
These instructions are required for execute only code
so NoMovt should be disabled when that option is enabled.

Differential Revision: https://reviews.llvm.org/D52551

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@343302 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/ARM/ARMSubtarget.cpp b/lib/Target/ARM/ARMSubtarget.cpp
index 1c17b63..b1d0761 100644 (file)
--- a/lib/Target/ARM/ARMSubtarget.cpp
+++ b/lib/Target/ARM/ARMSubtarget.cpp
@@ -188,8 +188,10 @@ void ARMSubtarget::initSubtargetFeatures(StringRef CPU, StringRef FS) {
   assert(hasV6T2Ops() || !hasThumb2());
 
   // Execute only support requires movt support
-  if (genExecuteOnly())
-    assert(hasV8MBaselineOps() && !NoMovt && "Cannot generate execute-only code for this target");
+  if (genExecuteOnly()) {
+    NoMovt = false;
+    assert(hasV8MBaselineOps() && "Cannot generate execute-only code for this target");
+  }
 
   // Keep a pointer to static instruction cost data for the specified CPU.
   SchedModel = getSchedModelForCPU(CPUString);

diff --git a/test/CodeGen/ARM/execute-only-big-stack-frame.ll b/test/CodeGen/ARM/execute-only-big-stack-frame.ll
index 24c6a06..5e4e718 100644 (file)
--- a/test/CodeGen/ARM/execute-only-big-stack-frame.ll
+++ b/test/CodeGen/ARM/execute-only-big-stack-frame.ll
@@ -2,6 +2,8 @@
 ; RUN:  | FileCheck --check-prefix=CHECK-SUBW-ADDW %s
 ; RUN: llc < %s -mtriple=thumbv8m.base -mattr=+execute-only -O0 %s -o - \
 ; RUN:  | FileCheck --check-prefix=CHECK-MOVW-MOVT-ADD %s
+; RUN: llc < %s -mtriple=thumbv8m.base -mcpu=cortex-m23 -mattr=+execute-only -O0 %s -o - \
+; RUN:  | FileCheck --check-prefix=CHECK-MOVW-MOVT-ADD %s
 ; RUN: llc < %s -mtriple=thumbv8m.main -mattr=+execute-only -O0 %s -o - \
 ; RUN:  | FileCheck --check-prefix=CHECK-SUBW-ADDW %s
 

diff --git a/test/CodeGen/ARM/execute-only-section.ll b/test/CodeGen/ARM/execute-only-section.ll
index a3313d8..8c7eb0c 100644 (file)
--- a/test/CodeGen/ARM/execute-only-section.ll
+++ b/test/CodeGen/ARM/execute-only-section.ll
@@ -1,5 +1,6 @@
 ; RUN: llc < %s -mtriple=thumbv7m -mattr=+execute-only %s -o - | FileCheck %s
 ; RUN: llc < %s -mtriple=thumbv8m.base -mattr=+execute-only %s -o - | FileCheck %s
+; RUN: llc < %s -mtriple=thumbv8m.base -mcpu=cortex-m23 -mattr=+execute-only %s -o - | FileCheck %s
 ; RUN: llc < %s -mtriple=thumbv8m.main -mattr=+execute-only %s -o - | FileCheck %s
 
 ; CHECK:     .section .text,"axy",%progbits,unique,0

diff --git a/test/CodeGen/ARM/execute-only.ll b/test/CodeGen/ARM/execute-only.ll
index 3f42ca3..169f44c 100644 (file)
--- a/test/CodeGen/ARM/execute-only.ll
+++ b/test/CodeGen/ARM/execute-only.ll
@@ -1,4 +1,5 @@
 ; RUN: llc -mtriple=thumbv8m.base-eabi -mattr=+execute-only %s -o - | FileCheck --check-prefix=CHECK --check-prefix=CHECK-T2BASE %s
+; RUN: llc -mtriple=thumbv8m.base-eabi -mcpu=cortex-m23 -mattr=+execute-only %s -o - | FileCheck --check-prefix=CHECK --check-prefix=CHECK-T2BASE %s
 ; RUN: llc -mtriple=thumbv7m-eabi      -mattr=+execute-only %s -o - | FileCheck --check-prefix=CHECK --check-prefix=CHECK-T2 %s
 ; RUN: llc -mtriple=thumbv8m.main-eabi -mattr=+execute-only %s -o - | FileCheck --check-prefix=CHECK --check-prefix=CHECK-T2 %s