arm: Use -masm-syntax-unified when compiling with gcc8 or newer

Annoyingly, this makes all of the '.S' files we compile get treated as
divided syntax, so we need to make the syntax in them explicit.

Change-Id: I56a3916b7b24c84a1214a5d6bc4ed4d651f002cf

17 files changed, 43 insertions, 3 deletions

diff --git a/apps/plugins/mpegplayer/libmpeg2/idct_arm.S b/apps/plugins/mpegplayer/libmpeg2/idct_arm.S
index 90eb5031c7..8ff7c90629 100644
--- a/apps/plugins/mpegplayer/libmpeg2/idct_arm.S
+++ b/apps/plugins/mpegplayer/libmpeg2/idct_arm.S
@@ -21,6 +21,8 @@
 
 #include "config.h"
 
+    .syntax     unified
+
     .global     mpeg2_idct_copy
     .type       mpeg2_idct_copy, %function
     .global     mpeg2_idct_add
diff --git a/apps/plugins/mpegplayer/libmpeg2/idct_armv6.S b/apps/plugins/mpegplayer/libmpeg2/idct_armv6.S
index a259721410..ad28cefcf2 100644
--- a/apps/plugins/mpegplayer/libmpeg2/idct_armv6.S
+++ b/apps/plugins/mpegplayer/libmpeg2/idct_armv6.S
@@ -21,6 +21,8 @@
 
 #include "config.h"
 
+    .syntax unified
+
     .global     mpeg2_idct_copy
     .type       mpeg2_idct_copy, %function
     .global     mpeg2_idct_add
diff --git a/apps/recorder/jpeg_idct_arm.S b/apps/recorder/jpeg_idct_arm.S
index 1f2603da1b..e706a17384 100644
--- a/apps/recorder/jpeg_idct_arm.S
+++ b/apps/recorder/jpeg_idct_arm.S
@@ -24,6 +24,8 @@
 #include "config.h"
 #include "apps/core_asmdefs.h"
 
+    .syntax unified
+
     .section .text
     .align   2
     .global jpeg_idct1h
diff --git a/firmware/asm/arm/lcd-as-memframe.S b/firmware/asm/arm/lcd-as-memframe.S
index d42b2a920d..f69f6e5080 100644
--- a/firmware/asm/arm/lcd-as-memframe.S
+++ b/firmware/asm/arm/lcd-as-memframe.S
@@ -24,6 +24,8 @@
 #include "config.h"
 #include "cpu.h"
 
+     .syntax     unified
+
 /****************************************************************************
  * void lcd_copy_buffer_rect(fb_data *dst, fb_data *src, int width,
  *                           int height);
diff --git a/firmware/asm/arm/memcpy.S b/firmware/asm/arm/memcpy.S
index 86fc6b7930..1fbb6660e9 100644
--- a/firmware/asm/arm/memcpy.S
+++ b/firmware/asm/arm/memcpy.S
@@ -35,6 +35,8 @@
 #define push            lsr
 #endif
 
+    .syntax     unified
+
 /* Prototype: void *memcpy(void *dest, const void *src, size_t n); */
 /* Prototype: void *mempcpy(void *dest, const void *src, size_t n); */
 
diff --git a/firmware/asm/arm/memmove.S b/firmware/asm/arm/memmove.S
index e5c9b42928..cf22a74622 100644
--- a/firmware/asm/arm/memmove.S
+++ b/firmware/asm/arm/memmove.S
@@ -35,6 +35,8 @@
 #define push            lsr
 #endif
 
+        .syntax unified
+
         .text
 
 /*
diff --git a/firmware/asm/arm/memset.S b/firmware/asm/arm/memset.S
index d727f2a5ec..ef5cdb5819 100644
--- a/firmware/asm/arm/memset.S
+++ b/firmware/asm/arm/memset.S
@@ -20,6 +20,8 @@
  ****************************************************************************/
 #include "config.h"
 
+    .syntax unified
+
     .section    .icode,"ax",%progbits
 
     .align      2
diff --git a/firmware/asm/arm/memset16.S b/firmware/asm/arm/memset16.S
index 226eac39e1..851b9207a2 100644
--- a/firmware/asm/arm/memset16.S
+++ b/firmware/asm/arm/memset16.S
@@ -20,6 +20,8 @@
  ****************************************************************************/
 #include "config.h"
 
+    .syntax unified
+
     .section    .icode,"ax",%progbits
 
     .align      2
diff --git a/firmware/export/config.h b/firmware/export/config.h
index 80d59ea836..9812db9161 100644
--- a/firmware/export/config.h
+++ b/firmware/export/config.h
@@ -1018,14 +1018,19 @@ Lyre prototype 1 */
  * These macros are for switching on unified syntax in inline assembly.
  * Older versions of GCC emit assembly in divided syntax with no option
  * to enable unified syntax.
- *
- * FIXME: This needs to be looked at after the toolchain bump
  */
+#if (__GNUC__ < 8)
 #define BEGIN_ARM_ASM_SYNTAX_UNIFIED ".syntax unified\n"
 #define END_ARM_ASM_SYNTAX_UNIFIED   ".syntax divided\n"
+#else
+#define BEGIN_ARM_ASM_SYNTAX_UNIFIED
+#define END_ARM_ASM_SYNTAX_UNIFIED
+#endif
 
 #if defined(CPU_ARM) && defined(__ASSEMBLER__)
+#if (__GNUC__ < 8)
 .syntax unified
+#endif
 /* ARMv4T doesn't switch the T bit when popping pc directly, we must use BX */
 .macro ldmpc cond="", order="ia", regs
 #if ARM_ARCH == 4 && defined(USE_THUMB)
@@ -1043,6 +1048,9 @@ Lyre prototype 1 */
     ldr\cond pc, [sp], #4
 #endif
 .endm
+#if (__GNUC__ < 8)
+.syntax divided
+#endif
 #endif
 
 #if defined(CPU_COLDFIRE) && defined(__ASSEMBLER__)
diff --git a/firmware/target/arm/ata-as-arm.S b/firmware/target/arm/ata-as-arm.S
index 16c2928bf1..cec4a7e235 100644
--- a/firmware/target/arm/ata-as-arm.S
+++ b/firmware/target/arm/ata-as-arm.S
@@ -21,6 +21,7 @@
 
 #include "config.h"
 
+    .syntax unified
 
 #if CONFIG_CPU == PP5002
     /* Causes ATA retries on iPod G3 probably related to improper controller
diff --git a/lib/arm_support/support-arm.S b/lib/arm_support/support-arm.S
index 3af0c70975..d12392eeb3 100644
--- a/lib/arm_support/support-arm.S
+++ b/lib/arm_support/support-arm.S
@@ -30,6 +30,8 @@
 
 #include <config.h>
 
+.syntax unified
+
 .macro ARM_SDIV32_PRE numerator, divisor, sign
     /* sign[31] = divisor sign */
     ands    \sign, \divisor, #1<<31
diff --git a/lib/rbcodec/codecs/demac/libdemac/udiv32_arm.S b/lib/rbcodec/codecs/demac/libdemac/udiv32_arm.S
index 1d19160a91..514bae2949 100644
--- a/lib/rbcodec/codecs/demac/libdemac/udiv32_arm.S
+++ b/lib/rbcodec/codecs/demac/libdemac/udiv32_arm.S
@@ -29,6 +29,9 @@
  ****************************************************************************/
 
 #include "config.h"
+
+.syntax unified
+
 /* On targets with codec iram, a header file will be generated after an initial
    link of the APE codec, stating the amount of IRAM remaining for use by the
    reciprocal lookup table. */
diff --git a/lib/rbcodec/codecs/libtta/filter_arm.S b/lib/rbcodec/codecs/libtta/filter_arm.S
index 10f1491796..d801a52419 100644
--- a/lib/rbcodec/codecs/libtta/filter_arm.S
+++ b/lib/rbcodec/codecs/libtta/filter_arm.S
@@ -26,6 +26,8 @@
  * void hybrid_filter(fltst *fs, int *in)
  */
 
+    .syntax unified
+
 #ifdef USE_IRAM
     .section .icode, "ax", %progbits
 #else
diff --git a/lib/rbcodec/dsp/dsp_arm.S b/lib/rbcodec/dsp/dsp_arm.S
index 864abee4b6..b17c94fe6c 100644
--- a/lib/rbcodec/dsp/dsp_arm.S
+++ b/lib/rbcodec/dsp/dsp_arm.S
@@ -22,6 +22,7 @@
  ****************************************************************************/
  #include "rbcodecconfig.h"
 
+    .syntax unified
 /****************************************************************************
  *  void channel_mode_proc_mono(struct dsp_proc_entry *this,
  *                              struct dsp_buffer **buf_p)
diff --git a/lib/rbcodec/dsp/dsp_arm_v6.S b/lib/rbcodec/dsp/dsp_arm_v6.S
index aa27ec90f6..facd3facbd 100644
--- a/lib/rbcodec/dsp/dsp_arm_v6.S
+++ b/lib/rbcodec/dsp/dsp_arm_v6.S
@@ -20,6 +20,7 @@
  ****************************************************************************/
  #include "rbcodecconfig.h"
 
+ .syntax unified
 /****************************************************************************
  *  void sample_output_mono(struct sample_io_data *this,
  *                          struct dsp_buffer *src,
diff --git a/lib/unwarminder/safe_read.S b/lib/unwarminder/safe_read.S
index ce4913870c..557f3dca31 100644
--- a/lib/unwarminder/safe_read.S
+++ b/lib/unwarminder/safe_read.S
@@ -20,6 +20,8 @@
  ****************************************************************************/
 #include "config.h"
 
+.syntax unified
+
 .data
 was_aborted:
     .word   0
diff --git a/tools/configure b/tools/configure
index 8a2e499a29..be4b0e3902 100755
--- a/tools/configure
+++ b/tools/configure
@@ -4533,7 +4533,11 @@ if [ -z "$arch" ]; then
     elif [ -n "$(echo $cpp_defines | grep -w __arm__)" ]; then
         arch="arm"
         # cpp defines like "#define __ARM_ARCH_4TE__ 1" (where we want to extract the 4)
-        arch_version="$(echo $cpp_defines | tr ' ' '\012' | grep __ARM_ARCH | sed -e 's,.*\([0-9]\).*,\1,' | grep -v __ARM_ARCH)"
+        arch_version="$(echo $cpp_defines | tr ' ' '\012' | grep __ARM_ARCH | sed -e 's,.*\([0-9]\).*,\1,' | grep -v __ARM_ARCH | head -1)"
+        if test "$gccnum" -ge "800"; then
+            # GCC8+ can natively emit unified asm syntax
+            GCCOPTS="$GCCOPTS -masm-syntax-unified"
+        fi
     elif [ -n "$(echo $cpp_defines | grep -w __mips__)" ]; then
         arch="mips"
         arch_version="$(echo $cpp_defines | tr ' ' '\012' | grep _MIPS_ARCH_MIPS | sed -e 's,.*\([0-9][0-9]\).*,\1,' | grep -v _MIPS_ARCH_MIPS)"