Build 64bit browser for Android with clang for ARMv8

third_party/WebKit/Source/platform/audio/DenormalDisabler.h

Index: third_party/WebKit/Source/platform/audio/DenormalDisabler.h
diff --git a/third_party/WebKit/Source/platform/audio/DenormalDisabler.h b/third_party/WebKit/Source/platform/audio/DenormalDisabler.h
index c0d5cc842c5172b2c9d92290f90ba1c6657d0bf7..355b53ceb81a390885955cd71405e738d7ec879a 100644
--- a/third_party/WebKit/Source/platform/audio/DenormalDisabler.h
+++ b/third_party/WebKit/Source/platform/audio/DenormalDisabler.h
@@ -131,7 +131,7 @@ private:
     {
         int result;
 #if CPU(ARM64)
-        asm volatile("mrs %[result], FPCR" : [result] "=r" (result));
+        asm volatile("mrs %x[result], FPCR" : [result] "=r" (result));

[Raymond Toy, 2016/04/14 15:49:38]

So "result" is basically an integer so %x[result] is a 64-bit register?  Would
it be better to declare result to be int64_t instead of just plain int (line
132)?

Also, isn't the FPCR register just 32 bits long?  Then it doesn't matter if it's
stored in a 32-bit or 64-bit register?

[khasim.mohammed, 2016/04/14 16:38:46]

If I set this flag, -Wno-asm-operand-widths then this might not be needed. Let
me check again on this.

 #else
         asm volatile("vmrs %[result], FPSCR" : [result] "=r" (result));

[Nico, 2016/04/14 15:43:55]

should this grow an x too?

[khasim.mohammed, 2016/04/14 16:38:46]

Not required to 32bit.

 #endif
@@ -141,7 +141,7 @@ private:
     inline void setStatusWord(int a)
     {
 #if CPU(ARM64)
-        asm volatile("msr FPCR, %[src]" : : [src] "r" (a));
+        asm volatile("msr FPCR, %x[src]" : : [src] "r" (a));
 #else
         asm volatile("vmsr FPSCR, %[src]" : : [src] "r" (a));

[Nico, 2016/04/14 15:43:55]

same question

[khasim.mohammed, 2016/04/14 16:38:46]

No not required for 32bit

 #endif