diff options
author | Andrew Hsieh <andrewhsieh@google.com> | 2012-11-05 23:23:27 -0800 |
---|---|---|
committer | Gerrit Code Review <noreply-gerritcodereview@google.com> | 2012-11-05 23:23:28 -0800 |
commit | 1724e02fae2f5a2de04e994567a8c74cd31068ef (patch) | |
tree | 79a4558ce6daec9ac902e1846e90ec94d904fa88 | |
parent | c796025f7dc5f8df7c0f9c76bcaee96a7716912d (diff) | |
parent | af537b8206a515f942e5ee0338113bd485b55eb7 (diff) | |
download | android_external_v8-1724e02fae2f5a2de04e994567a8c74cd31068ef.tar.gz android_external_v8-1724e02fae2f5a2de04e994567a8c74cd31068ef.tar.bz2 android_external_v8-1724e02fae2f5a2de04e994567a8c74cd31068ef.zip |
Merge "Fix ARM hardfloat detection in linux"
-rw-r--r-- | src/platform-linux.cc | 71 |
1 files changed, 33 insertions, 38 deletions
diff --git a/src/platform-linux.cc b/src/platform-linux.cc index 9781407e..6c4a549c 100644 --- a/src/platform-linux.cc +++ b/src/platform-linux.cc @@ -190,48 +190,43 @@ bool OS::ArmCpuHasFeature(CpuFeature feature) { } -// Simple helper function to detect whether the C code is compiled with -// option -mfloat-abi=hard. The register d0 is loaded with 1.0 and the register -// pair r0, r1 is loaded with 0.0. If -mfloat-abi=hard is pased to GCC then -// calling this will return 1.0 and otherwise 0.0. -static void ArmUsingHardFloatHelper() { - asm("mov r0, #0":::"r0"); -#if defined(__VFP_FP__) && !defined(__SOFTFP__) - // Load 0x3ff00000 into r1 using instructions available in both ARM - // and Thumb mode. - asm("mov r1, #3":::"r1"); - asm("mov r2, #255":::"r2"); - asm("lsl r1, r1, #8":::"r1"); - asm("orr r1, r1, r2":::"r1"); - asm("lsl r1, r1, #20":::"r1"); - // For vmov d0, r0, r1 use ARM mode. -#ifdef __thumb__ - asm volatile( - "@ Enter ARM Mode \n\t" - " adr r3, 1f \n\t" - " bx r3 \n\t" - " .ALIGN 4 \n\t" - " .ARM \n" - "1: vmov d0, r0, r1 \n\t" - "@ Enter THUMB Mode\n\t" - " adr r3, 2f+1 \n\t" - " bx r3 \n\t" - " .THUMB \n" - "2: \n\t":::"r3"); +bool OS::ArmUsingHardFloat() { + // GCC versions 4.6 and above define __ARM_PCS or __ARM_PCS_VFP to specify + // the Floating Point ABI used (PCS stands for Procedure Call Standard). + // We use these as well as a couple of other defines to statically determine + // what FP ABI used. + // GCC versions 4.4 and below don't support hard-fp. + // GCC versions 4.5 may support hard-fp without defining __ARM_PCS or + // __ARM_PCS_VFP. + +#define GCC_VERSION (__GNUC__ * 10000 \ + + __GNUC_MINOR__ * 100 \ + + __GNUC_PATCHLEVEL__) +#if GCC_VERSION >= 40600 +#if defined(__ARM_PCS_VFP) + return true; #else - asm("vmov d0, r0, r1"); -#endif // __thumb__ -#endif // defined(__VFP_FP__) && !defined(__SOFTFP__) - asm("mov r1, #0":::"r1"); -} + return false; +#endif +#elif GCC_VERSION < 40500 + return false; -bool OS::ArmUsingHardFloat() { - // Cast helper function from returning void to returning double. - typedef double (*F)(); - F f = FUNCTION_CAST<F>(FUNCTION_ADDR(ArmUsingHardFloatHelper)); - return f() == 1.0; +#else +#if defined(__ARM_PCS_VFP) + return true; +#elif defined(__ARM_PCS) || defined(__SOFTFP) || !defined(__VFP_FP__) + return false; +#else +#error "Your version of GCC does not report the FP ABI compiled for." \ + "Please report it on this issue" \ + "http://code.google.com/p/v8/issues/detail?id=2140" + +#endif +#endif +#undef GCC_VERSION } + #endif // def __arm__ |