RFR: 8318078: ADLC: pass ASSERT and PRODUCT flags

[Vladimir Kozlov]

On Fri, 13 Oct 2023 09:49:48 GMT, Emanuel Peter <epeter at openjdk.org> wrote:

> @vnkozlov asked me to guard some debug AD file rules in `#ifdef ASSERT`. https://github.com/openjdk/jdk/pull/14785#discussion_r1349391130
> 
> We discovered that the `ASSERT` and `PRODUCT` are not yet passed to ADLC, and hence they are always considered `undefined`. Hence, all of these `ifdef` blocks would always be ignored.
> 
> **Solution**
> I added the flags to `make/hotspot/gensrc/GensrcAdlc.gmk`, just like in `make/hotspot/lib/JvmFlags.gmk`.
> 
> As @erikj79 commented: we should probably unify this. But I leave that to the build team.
> 
> **Testing**
> With this code you can see what flags are passed to ADLC:
> 
> --- a/src/hotspot/share/adlc/main.cpp
> +++ b/src/hotspot/share/adlc/main.cpp
> @@ -56,6 +56,11 @@ int main(int argc, char *argv[])
>    // Check for proper arguments
>    if( argc == 1 ) usage(AD);    // No arguments?  Then print usage
>  
> +  for( int i = 1; i < argc; i++ ) { // For all arguments
> +    char *s = argv[i];          // Get option/filename
> +    fprintf(stderr, "ARGV[%d] %s\n", i, s);
> +  }
> +
>    // Read command line arguments and file names
>    for( int i = 1; i < argc; i++ ) { // For all arguments
>      char *s = argv[i];          // Get option/filename
> 
> 
> On `linux-x64` I get:
> 
> ARGV[1] -q
> ARGV[2] -T
> ARGV[3] -DLINUX=1
> ARGV[4] -D_GNU_SOURCE=1
> ARGV[5] -g
> ARGV[6] -DAMD64=1
> ARGV[7] -D_LP64=1
> ARGV[8] -DNDEBUG
> ARGV[9] -DPRODUCT
> 
> 
> And on `linux-x64-debug` I get:
> 
> ARGV[1] -q
> ARGV[2] -T
> ARGV[3] -DLINUX=1
> ARGV[4] -D_GNU_SOURCE=1
> ARGV[5] -g
> ARGV[6] -DAMD64=1
> ARGV[7] -D_LP64=1
> ARGV[8] -DASSERT
> 
> 
> I verified that the `#ifdef` work as expected, by adding this code to `src/hotspot/cpu/x86/x86.ad`:
> 
> #ifdef ASSERT
> #ifdef PRODUCT
> control
> #endif
> #endif
> 
> #ifdef ASSERT
> xxx
> #endif
> 
> #ifdef PRODUCT
> yyy
> #endif
> 
> When compiling, I get complaints for `yyy` on `linux-x64` and for `xxx` on `linux-x64-debug`. But since `ASSERT` and `PRODUCT` never occur together, we never get complaints about `control`.
> 
> **Running tier1-3 and stress testing ...**

make/hotspot/gensrc/GensrcAdlc.gmk line 138:

> 136:   # Set ASSERT, NDEBUG and PRODUCT flags just like in JvmFlags.gmk
> 137:   ifeq ($(DEBUG_LEVEL), release)
> 138:     ADLCFLAGS += -DNDEBUG

May be you should also copy all comments from `JvmFlags.gmk` to avoid confusion because, for example, `NDEBUG` is not used directly in HotSpot code but it is needed "to disable uses of assert macro from <assert.h>."

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PR Review Comment: https://git.openjdk.org/jdk/pull/16178#discussion_r1358574163