MIPS compiler flags: use -mfp32, -mfp64, or -mfpxx only if -mhard-float

is used.

-mfp32, -mfp64, and -mfpxx only make sense if the FPU is used.

R=brettw@chromium.org,petarj@mips.com
BUG=446234

Review URL: https://codereview.chromium.org/975183002

Cr-Original-Commit-Position: refs/heads/master@{#319227}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 07fce68bd04aa5b28916f76173b0c6ead60eddde

common.gypi

@@ -2302,13 +2302,13 @@
         'arm_thumb%': 1,
       }],
 
-      # Set default compiler flags depending on MIPS architecture variant.
-      ['target_arch=="mipsel" and mips_arch_variant=="r2" and android_webview_build==0', {
-        'mips_fpu_mode%': 'fp32',
-      }],
+      # Set default compiler flags for MIPS floating-point support.
       ['target_arch=="mipsel" and android_webview_build==0', {
         'mips_float_abi%': 'hard',
       }],
+      ['target_arch=="mipsel" and mips_arch_variant=="r2" and android_webview_build==0', {
+        'mips_fpu_mode%': 'fp32',
+      }],
 
       ['android_webview_build==1', {
         # The WebView build gets its cpu-specific flags from the Android build system.
@@ -2317,8 +2317,8 @@
         'arm_fpu%': '',
         'arm_float_abi%': '',
         'arm_thumb%': 0,
-        'mips_fpu_mode%': '',
         'mips_float_abi%': '',
+        'mips_fpu_mode%': '',
       }],
 
       # Enable brlapi by default for chromeos.
@@ -4081,7 +4081,7 @@
                       ['mips_arch_variant=="r2"', {
                         'cflags': ['-mips32r2', '-Wa,-mips32r2'],
                         'conditions': [
-                          ['mips_fpu_mode!=""', {
+                          ['mips_float_abi=="hard" and mips_fpu_mode!=""', {
                             'cflags': ['-m<(mips_fpu_mode)'],
                           }],
                         ],

config/compiler/BUILD.gn

@@ -302,7 +302,7 @@ config("compiler") {
             "-mips32r2",
             "-Wa,-mips32r2",
           ]
-          if (mips_fpu_mode != "") {
+          if (mips_float_abi == "hard" && mips_fpu_mode != "") {
             cflags += [ "-m$mips_fpu_mode" ]
           }
         } else if (mips_arch_variant == "r1") {