[ARM] Fix endianness of Thumb .inst.w directive
Wide Thumb2 instructions should be emitted into the object file as pairs of
16-bit words of the appropriate endianness, not one 32-bit word.
Differential revision: https://reviews.llvm.org/D41185
llvm-svn: 321799
diff --git a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
index d465da1..9d73c76 100644
--- a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
+++ b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
@@ -512,9 +512,11 @@
assert(IsThumb);
EmitThumbMappingSymbol();
+ // Thumb wide instructions are emitted as a pair of 16-bit words of the
+ // appropriate endianness.
for (unsigned II = 0, IE = Size; II != IE; II = II + 2) {
- const unsigned I0 = LittleEndian ? II + 0 : (Size - II - 1);
- const unsigned I1 = LittleEndian ? II + 1 : (Size - II - 2);
+ const unsigned I0 = LittleEndian ? II + 0 : II + 1;
+ const unsigned I1 = LittleEndian ? II + 1 : II + 0;
Buffer[Size - II - 2] = uint8_t(Inst >> I0 * CHAR_BIT);
Buffer[Size - II - 1] = uint8_t(Inst >> I1 * CHAR_BIT);
}
diff --git a/llvm/test/MC/ARM/inst-directive.s b/llvm/test/MC/ARM/inst-directive.s
index a3fd8c2..d3f2a36 100644
--- a/llvm/test/MC/ARM/inst-directive.s
+++ b/llvm/test/MC/ARM/inst-directive.s
@@ -1,5 +1,8 @@
@ RUN: llvm-mc %s -triple=armv7-linux-gnueabi -filetype=obj -o - \
-@ RUN: | llvm-readobj -s -sd | FileCheck %s
+@ RUN: | llvm-readobj -s -sd | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-LE
+
+@ RUN: llvm-mc %s -triple=armebv7-linux-gnueabi -filetype=obj -o - \
+@ RUN: | llvm-readobj -s -sd | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-BE
.syntax unified
@@ -19,7 +22,8 @@
@ CHECK: Section {
@ CHECK: Name: .inst.arm_inst
@ CHECK: SectionData (
-@ CHECK-NEXT: 0000: FEDE0000
+@ CHECK-LE-NEXT: 0000: FEDE0000
+@ CHECK-BE-NEXT: 0000: 0000DEFE
@ CHECK-NEXT: )
@-------------------------------------------------------------------------------
@@ -38,7 +42,8 @@
@ CHECK: Section {
@ CHECK: Name: .inst.thumb_inst_n
@ CHECK: SectionData (
-@ CHECK-NEXT: 0000: FEDE
+@ CHECK-LE-NEXT: 0000: FEDE
+@ CHECK-BE-NEXT: 0000: DEFE
@ CHECK-NEXT: )
@-------------------------------------------------------------------------------
@@ -52,12 +57,13 @@
.global thumb_inst_w
.type thumb_inst_w,%function
thumb_inst_w:
- .inst.w 0x00000000
+ .inst.w 0x12345678
@ CHECK: Section {
@ CHECK: Name: .inst.thumb_inst_w
@ CHECK: SectionData (
-@ CHECK-NEXT: 0000: 00000000
+@ CHECK-LE-NEXT: 0000: 34127856
+@ CHECK-BE-NEXT: 0000: 12345678
@ CHECK-NEXT: )
@-------------------------------------------------------------------------------
@@ -76,6 +82,7 @@
@ CHECK: Section {
@ CHECK: Name: .inst.thumb_inst_inst
@ CHECK: SectionData (
-@ CHECK-NEXT: 0000: 40F20000 C0F20000
+@ CHECK-LE-NEXT: 0000: 40F20000 C0F20000
+@ CHECK-BE-NEXT: 0000: F2400000 F2C00000
@ CHECK-NEXT: )