[ARM] Support fixup for Thumb2 modified immediate

    
This change adds a new fixup fixup_t2_so_imm for the t2_so_imm_asmoperand
"T2SOImm". The fixup permits code such as:
.L1:
 sub r3, r3, #.L2 - .L1
.L2:
to assemble in Thumb2 as well as in ARM state.
    
The operand predicate isT2SOImm() explicitly doesn't match expressions
containing :upper16: and :lower16: as expressions with these operators
must match the movt and movw instructions.
    
The test mov r0, foo2 in thumb2-diagnostics is moved to a new file as the
fixup delays the error message till after the assembler has quit due to
the other errors.
    
As the mov instruction shares the t2_so_imm_asmoperand mov instructions
with a non constant expression now match t2MOVi rather than t2MOVi16 so the
error message is slightly different.
    
Fixes PR28647

Differential Revision: https://reviews.llvm.org/D33492

llvm-svn: 304702

5 files changed, 76 insertions, 2 deletions

diff --git a/llvm/test/MC/ARM/big-endian-thumb2-fixup.s b/llvm/test/MC/ARM/big-endian-thumb2-fixup.s
index 0aaa26a209f..4435f6ed79e 100644
--- a/llvm/test/MC/ARM/big-endian-thumb2-fixup.s
+++ b/llvm/test/MC/ARM/big-endian-thumb2-fixup.s
@@ -47,3 +47,9 @@ ldst_precel_12_label:
 	nop
 adr_pcrel_12_label:
 
+@ARM::fixup_t2_so_imm
+.section s_t2_so_imm,"ax",%progbits
+// CHECK-LABEL: Contents of section s_t2_so_imm
+// CHECK: 0000 f1033337
+	add r3, r3,val
+.equ val,0x37373737
diff --git a/llvm/test/MC/ARM/t2-modified-immediate-fixup-error1.s b/llvm/test/MC/ARM/t2-modified-immediate-fixup-error1.s
new file mode 100644
index 00000000000..f5113a64920
--- /dev/null
+++ b/llvm/test/MC/ARM/t2-modified-immediate-fixup-error1.s
@@ -0,0 +1,13 @@
+@ PR28647
+@ RUN: not llvm-mc -triple=thumbv7a-linux-gnueabi -filetype=obj < %s 2>&1 | FileCheck %s
+    .text
+    .syntax unified
+    .balign 2
+
+@ Error with unencodeable immediate
+    add r1, r2, sym0
+@ CHECK: error: out of range immediate fixup value
+    .equ sym0, 0x01abcdef
+.L2:
+    mov r0, .L2
+@ CHECK: error: unsupported relocation on symbol
diff --git a/llvm/test/MC/ARM/t2-modified-immediate-fixup-error2.s b/llvm/test/MC/ARM/t2-modified-immediate-fixup-error2.s
new file mode 100644
index 00000000000..a5672b5eb1f
--- /dev/null
+++ b/llvm/test/MC/ARM/t2-modified-immediate-fixup-error2.s
@@ -0,0 +1,12 @@
+@ PR28647
+@ RUN: not llvm-mc -triple=thumbv7a-linux-gnueabi -filetype=obj < %s 2>&1 | FileCheck %s
+    .text
+    .syntax unified
+    .balign 2
+
+@ mov with :upper16: or :lower16: should not match mov with modified immediate
+    mov r0, :upper16: sym0
+@ CHECK: error: instruction requires: arm-mode
+    mov r0, :lower16: sym0
+@ CHECK: error: instruction requires: arm-mode
+    .equ sym0, 0x01abcdef
diff --git a/llvm/test/MC/ARM/t2-modified-immediate-fixup.s b/llvm/test/MC/ARM/t2-modified-immediate-fixup.s
new file mode 100644
index 00000000000..ad0fae2e666
--- /dev/null
+++ b/llvm/test/MC/ARM/t2-modified-immediate-fixup.s
@@ -0,0 +1,45 @@
+@ PR28647
+@ RUN: llvm-mc < %s -triple=thumbv7a-linux-gnueabi -filetype=obj -o - \
+@ RUN: | llvm-objdump --disassemble -triple=thumbv7a-linux-gnueabi - | FileCheck %s
+    .text
+    .syntax unified
+    .balign 2
+@ Thumb2 modified immediate instructions
+    add r1,r1, sym0
+    sub r1,r2, sym1
+    cmp r2,    sym2
+    and r4,r4, sym3
+    orr r8,r9, sym4
+    teq r1,    sym5
+    tst r1,    sym6
+    sbc r1,r1, sym7
+    adc r1,r0, sym8
+@CHECK: add.w   r1, r1, #255
+@CHECK: sub.w   r1, r2, #16711935
+@CHECK: cmp.w   r2, #4278255360
+@CHECK: and     r4, r4, #303174162
+@CHECK: orr     r8, r9, #2852126720
+@CHECK: teq.w   r1, #1426063360
+@CHECK: tst.w   r1, #713031680
+@CHECK: sbc     r1, r1, #2785280
+@CHECK: adc     r1, r0, #340
+
+.L1:
+    sub r3, r3, #.L2 - .L1
+.L2:
+@CHECK: sub.w   r3, r3, #4
+
+@ mov without :upper16: or :lower16: should match mov with modified immediate
+     mov r1, sym3
+@CHECK: mov.w   r1, #303174162
+
+@ Modified immediate constants
+    .equ sym0, 0x000000ff
+    .equ sym1, 0x00ff00ff
+    .equ sym2, 0xff00ff00
+    .equ sym3, 0x12121212
+    .equ sym4, 0xaa000000
+    .equ sym5, 0x55000000
+    .equ sym6, 0x2a800000
+    .equ sym7, 0x002a8000
+    .equ sym8, 0x00000154
diff --git a/llvm/test/MC/ARM/thumb2-diagnostics.s b/llvm/test/MC/ARM/thumb2-diagnostics.s
index 76b4cf12626..ca917a0502d 100644
--- a/llvm/test/MC/ARM/thumb2-diagnostics.s
+++ b/llvm/test/MC/ARM/thumb2-diagnostics.s
@@ -76,10 +76,8 @@
 @ CHECK-ERRORS: error: branch target out of range
 
 foo2:
-        mov r0, foo2
         movw r0, foo2
         movt r0, foo2
-@ CHECK-ERRORS: error: instruction requires: arm-mode
 @ CHECK-ERRORS: error: immediate expression for mov requires :lower16: or :upper16
 @ CHECK-ERRORS:                  ^
 @ CHECK-ERRORS: error: immediate expression for mov requires :lower16: or :upper16